View Report And Attachment 1 — Oakland City Council, September 15, 2025

City Council
September 15, 2025

RECOMMENDATION

AGENDA REPORT
The City Administration Recommends That, After Conducting A Public Hearing And Upon Conclusion, The City Council Adopt The Following Pieces of Legislation:
(1) An Ordinance: (1) Adding Oakland Municipal Code (“O.M.C.”) Chapter

15.06, “Oakland Amendments to the California Energy and Green Building Codes,” Related To Building Decarbonization, Energy Efficiency, And Public Health To Meet the City of Oakland’s Resource Conservation and Climate Goals; (2) Repealing The City Of Oakland’s Local Amendments To The 2022 Edition Of The California Energy Code (Title 24, Part 6) And The 2022 California Green Building Code (Title 24, Part 11) at O.M.C. Chapter 15.04, Part 6 and Part 11 Administrative and Technical Amendments; And (3) Adopting Appropriate California Environmental Quality Act Findings; And (2) A Resolution Of Findings Supporting The Adoption Of An Ordinance:
(1) Adding Oakland Municipal Code (“O.M.C.”) Chapter 15.06, “Oakland Amendments to the California Energy and Green Building Codes” To O.M.C.

Title 15, “Buildings and Construction;” (2) Repealing The City Of Oakland’s Local Amendments To The 2022 Edition Of The California Energy Code (Title 24, Part 6) And The 2022 California Green Building Code (Title 24, Part 11); And (3) Adopting Appropriate California Environmental Quality Act Exemption Findings.

EXECUTIVE SUM
MARY

The proposed legislation would adopt new City of Oakland (City) amendments to the 2025 California Energy Code and Green Building Standards Code (CALGreen) to implement the City’s 2030 Equitable Climate Action Plan (ECAP) (CMS 88267) and General Plan TO: Jestin D. Johnson FROM: William A. Gilchrist
City Administrator Director, Planning and
Building Department
SUBJECT: Adoption of Local Amendments For
Energy and Green Building Codes
Related to Decarbonization, Energy
Efficiency, and Public Health
DATE: September 8, 2025

City Administrator Approval Date:

Jestin Johnson (Sep 11, 2025 15:19:24 PDT)
Sep 11, 2025
Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 2
City Council
September 15, 2025

Environmental Justice (EJ) Element goals (CMS 89907). The proposed amendments establish a comprehensive framework to reduce greenhouse gas (GHG) emissions and improve public health in both new and existing buildings.

The City Council adopted the EJ Element as part of Phase One of the City’s General Plan Update on June 21, 2023. The EJ Element serves to equitably advance the health and safety of the City’s residents and businesses. and explicitly references and integrates the goals and strategies of the City’s ECAP. In alignment with the City's adopted greenhouse gas emissions reduction strategy, the EJ Element supports the transition to all-electric buildings.

The proposed Ordinance is exempt from the California Environmental Quality Act (CEQA) on the grounds that its regulatory standards are more stringent than those in the State Building Standards Code (Building Code) and is a regulatory action for the protection of the environment.

As a result, there is no reasonably foreseeable adverse impacts associated with these higher standards. The findings supporting the proposed Ordinance are set forth in the proposed Resolution.

BACKGROUND / LEGISLATIVE HISTORY
The City has been a leader in ambitious and equity-driven climate action for decades, frequently surpassing California statewide goals. Resolution No. 82129 C.M.S. (2009) directed staff to develop the City’s first climate strategy - the 2020 Energy and Climate Action Plan - with a GHG emission reduction target of 36 percent below 2005 levels; it also established a long-term GHG reduction target of 83 percent by 2050. In 2015, as a signatory to the Under2 Memorandum of Understanding and the Global Covenant of Mayors, the City declared its commitment to reducing its GHG emissions to levels consistent with the targets established in the 2015 Paris Climate Accord.

In 2016, California enacted Senate Bill (SB) 32, which built on the 2006 California Global Warming Solutions Act by requiring Statewide GHG emissions be reduced to 40 percent below 1990 levels by 2030. In 2018, the Oakland City Council adopted Resolution No. 87183 C.M.S., establishing a GHG emissions reduction target of 56 percent below 2005 levels by 2030. The City Council also adopted Resolution No. 87397 C.M.S. in 2018, declaring a climate emergency and calling for regional collaboration and a “citywide just transition and urgent climate mobilization effort to reverse global warming … as quickly as possible towards zero net emissions.”

In July 2020, the City Council adopted the 2030 ECAP, a comprehensive plan responsive to the abovementioned Resolutions. The ECAP addresses both GHG mitigation and climate resilience through an equity lens, leveraging the tools and policy levers available through the City’s regulatory and legal spheres of control to reduce local GHG emissions on a path projected to exceed Council’s adopted 2030 and 2050 reduction targets.

Alongside the 2030 ECAP, the City Council also adopted a Carbon Neutrality Target of 2045 (Resolution No. 88268 C.M.S.). Achieving carbon neutrality will require complete decarbonization (ensuring that all mechanical systems run on clean electricity) of Oakland’s building sector.

Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 3
City Council
September 15, 2025

Action B-2 (Plan for All Existing Buildings to be Efficient and All- Electric by 2040) in the 2030 ECAP directs staff to develop a policy roadmap to achieve decarbonization of the existing building stock by 2040, without additional cost burden or displacement risk to frontline communities. The roadmap must address:
• Equitable process and outcomes, including avoiding bill increases, ensuring benefits flow to renters, and local green jobs;
• Incentives and requirements;
• Regulatory obstacles;
• Phasing of implementation;
• Financial assistance for low-income residents and businesses, including on-bill financing;
• Opportunities for integration of distributed renewable energy generation and energy storage; and
• Opportunities and needs for energy efficiency and building envelope upgrades, taking into account local, state, and regional energy efficiency incentive programs and focusing particularly on renters, low-income populations, and populations with a disproportionate risk of housing and business displacement.

The local building code is an important tool for cities to further local climate goals, including those set forth in Oakland’s ECAP. Local jurisdictions are required to enforce the California Building Standards Code, codified as Title 24 of the California Code of Regulations (hereafter, Title 24), whether or not the jurisdiction formally adopts the Code. Title 24, Part 6, governs energy and energy efficiency in residential and nonresidential buildings and Title 24, Part 11, governs green buildings measures.

Local jurisdictions are permitted to adopt local amendments that exceed the State building code to address local conditions. Local jurisdictions may not adopt or implement less stringent standards. California Health & Safety Code Section 17958.7 provides that before making any modifications to the California Green Building Standards Code or any other applicable provisions published by the State Building Standards Commission, a governing body must make an express finding that each such change or modification is reasonably necessary because of specified local conditions. The findings must be filed with the State Building Standards Commission before the local changes or modifications go into effect. The recommended findings are set forth in the proposed Resolution.

ANALYSIS AND POLICY ALTERNATIVES

The City’s 2017 Climate Action for Urban Sustainability (CURB) analysis indicated the City would not achieve its GHG emission reduction targets without eliminating natural gas combustion in buildings. However, the recent Ninth Circuit decision in California Restaurant Association v. City of Berkeley held that local legislation requiring buildings be all-electric, as opposed to incentivizing electrification, is preempted by the federal Energy Policy and Conservation Act (“EPCA”).
1 As such, the City is not proposing an all-electric requirement for

1 See Docket No. 21-16278, 89 F.4th 1094 (9th Cir. January 2, 2024).

new or existing buildings within the City. Instead, the City’s local amendments focus on preparing buildings for future electrification that results in actual cost reductions.

In 2017, the most recent year for which data is available, 25.8 percent of Oakland’s local GHG emissions originated from buildings, of which more than 70 percent came from natural gas combustion. That same analysis listed electrification of building space- heating systems as one of the top five strategic actions necessary to achieve those goals.

Oakland’s primary source of electricity is East Bay Community Energy (EBCE), a local joint powers authority electricity supplier in Alameda County that prioritizes local renewable generation and local green jobs and development. EBCE’s electricity generation was 85 percent renewable in 2019 and likely to be fully renewable and carbon free well before 2030. Increases in Oakland’s consumption of electricity therefore draw from a clean and equitable electric grid, one that supports local economic development.

Failure to address and significantly reduce GHG emissions will result in continued increases in sea level rise that could put Oakland homes and businesses, public facilities, and portions of major local and regional transportation infrastructure at risk. Additional direct impacts of an unmitigated climate crisis likely to affect Oakland, as described in the Intergovernmental Panel on Climate Change (IPCC) reports and the 2030 ECAP, include severe weather events, increasing droughts, more frequent heat events and wildfires, smoke inundation from regional fires, erosion, flooding, and landslides.

Impacts of Natural Gas

Natural Gas and the Climate Crisis – Natural gas is primarily comprised of methane, a short- lived climate pollutant whose contribution to climate change (“global warming potential”) is 86 times greater than carbon dioxide. Stopping methane pollution is necessary to keep global warming below the 1.5 degree-Celsius target identified in the Paris Climate Accord and in the subsequent agreements to which Oakland is a signatory. Methane pollution happens throughout the natural gas system, from leakages at the point of extraction and along the distribution system, to incidental leakage within homes and buildings. Additional climate emissions occur when natural gas is burned in home and building appliances, including for cooking, clothes drying, water heating, and space heating.

The City cannot meet its climate goals without shifting away from predominantly natural gas use without preparing buildings for future electrification that results in actual cost reductions. State policies and lower prices of renewable energy mean that substituting natural gas with electricity is one of the quickest, safest, and least expensive pathways to eliminating GHG emissions from buildings.

Natural Gas and Public Health – Indoor natural gas use, particularly for cooking, worsens indoor air quality, which disproportionately harms frontline communities, i.e., communities that experience the first and worst consequences of climate change. Burning natural gas creates indoor air pollutants including carbon monoxide, formaldehyde, and nitrogen dioxide, all of which contribute to respiratory ailments. These impacts are compounded in small, poorly- ventilated spaces like older apartments. Children living in homes with gas cooking are 42 percent more likely to have asthma.

Natural Gas and Public Safety – Natural gas presents combustion risk for buildings, especially during and after major earthquakes. It is well known that gas pipelines can cause catastrophic disasters, with perhaps the most infamous example being the 2010 San Bruno explosion. In 2017, the U.S. Geological Survey conducted its “HayWired Scenario,” simulating a 7.0 quake on the Hayward fault line with the epicenter in Oakland. The agency’s report predicted that “about 450 large fires could result in a loss of residential and commercial building floor area equivalent to more than 52,000 single-family homes and cause property (building and content) losses approaching $30 billion.” The report identified ruptured gas lines as a key fire risk factor. This finding mirrors the reality of the destructive gas fires resulting from the 1989 Loma Prieta and 1994 Northridge earthquakes.

Natural Gas and Resilience – Gas lines are also more difficult to repair following disasters than electric infrastructure, and as such reduce a city’s resilience. In times of disaster, the fossil fuel supply chain will likely be disrupted. Conversely, preparing buildings for future electrification that results in actual cost reductions can increase resilience. Electric appliances in conjunction with battery storage technology and renewable energy generation (such as rooftop solar) can operate absent the grid’s electric supply chain. Moreover, newer gas appliances, such as stoves and water heaters, require electricity to start. Thus, in times of power outages, gas appliances in new buildings will not provide the resilience that many people desire.

Natural Gas and Disproportionate Pollution Burdens and Severe Health Disparities – the City’s,topography and history have created concentrated zones of severe air pollution, disproportionately impacting communities in West and East Oakland. • Statewide Pollution Hotspots: Four Oakland census tracts rank in the top 10th percentile in California for their cumulative pollution burden.
• Health Crisis: This pollution burden translates into devastating health outcomes.

Residents of West and Downtown Oakland experience significantly higher rates of asthma- related emergency room visits, and there is a nearly 20-year gap in life expectancy between the Oakland hills and the flatlands of West and East Oakland. • Indoor Air Quality: The ECAP and EJ Element highlight the contribution of indoor sources to these health crises, noting that "children who live in homes with gas stoves have a 42% increased chance of developing asthma" and that burning natural gas creates indoor pollutants like nitrogen dioxide (NO2) and carbon monoxide (CO).

A Comprehensive Approach for New and Existing Buildings The proposed ordinance combines amendments to both the Energy Code and CALGreen to create a holistic strategy:
• Energy Code (Part 6): Amendments will establish high-performance standards for new construction, using energy modeling metrics (EDR/Source Energy) to strongly incentivize all- electric designs in a legally durable manner.
• Energy Code (Part 6): Amendments will apply to existing residential building alterations with a permit valuation over $25,000, requiring the implementation of practical, cost-effective electrification and efficiency measures from a flexible menu of options. • CALGreen (Part 11): Amendments will apply to existing residential building alterations with a permit valuation over $25,000, requiring the implementation of all Mandatory Measures regardless of if a project is adding conditioned space, volume or size.

• CALGreen (Part 11): Amendments will require new construction to utilize concrete mixes that do not exceed a specified maximum Global Warming Potential (GWP) limit The Amendments are set forth in full in the proposed Ordinance. This dual approach ensures that the City is addressing emissions from all construction activities, accelerating progress toward its 2030 ECAP and 2040 existing building decarbonization goals.

The adoption of this ordinance and findings aims to meet the following citywide priorities of addressing climate resilience, holistic community safety and supporting vibrant sustainable infrastructure.

FISCAL IMPACT

There is no fiscal impact to the City. Resources from existing budgeted staff will continue to enforce the Model Construction Codes as amended by the City.

The cost implications for residents are as follows:
• Cost-Effectiveness of High-Performance New Construction Multiple analyses have concluded that all-electric new construction is cost-effective, often resulting in lower upfront costs due to the avoidance of gas infrastructure, which can cost between $7,050 and $9,500 for a single-family home. The performance standards in this ordinance are designed to make all-electric construction the most economically advantageous compliance pathway for developers.
• Cost-Effectiveness of Alteration Requirements
Requiring electrification-readiness and efficiency upgrades during a significant remodel is the most cost-effective time to undertake such work. The marginal cost of adding a 240-volt circuit or upgrading an electrical panel is significantly lower when walls are already open and electricians are on-site for other work. The ordinance provides a flexible menu of options, allowing property owners to choose the most practical and affordable measures for their specific project, thereby avoiding undue financial burden while preparing the home for a fossil-fuel-free future.

PUBLIC OUTREACH / INTEREST

The City engaged in extensive community and stakeholder outreach regarding building energy efficiency, electrification, and associated workforce implications through the ECAP and Phase 1 of the General Plan development process, development of the City’s 2020 building code update, and other targeted outreach led by the City and partners. This specifically included:
• 4,000+ Oaklanders weighing in on development of the ECAP, with a consensus that there be full electrification of the entire inventory of Oakland’s buildings, provided that it is predicated on efficiency and equitable implementation to ensure implementation does not exacerbate energy insecurity or housing displacement;
• ECAP ad-hoc Community Advisory Committee voted explicitly to advocate for equitable full electrification of all Oakland residential buildings; Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 7
City Council
September 15, 2025

• Targeted in-person and virtual events, documented on the City’s Building Electrification webpage, including:
o a 3- part virtual town hall series addressing workforce needs and opportunities from electrification (50-70 participants per workshop);
o Building Electrification Clubhouse, a monthly networking and learning event co- convened by the City, Building Industry Gathering Oakland, and the Association of Energy Affordability; and
o Pop-up community education at farmers markets, community centers, Oakland Roots soccer games, neighborhood meetings, and other events.

For new construction electrification specifically, the City convened workshops on June 13, 2019 and September 12, 2019, with stakeholders consisting of developers, heating, ventilation and air conditioning (HVAC) designers, contractors, architects, engineers, business leaders, and City staff. Individual interviews with stakeholders were also conducted between workshops.

For electrification of existing buildings, insights came from the online Electrification Workforce workshop series that Sustainability & Resilience Division, Economic & Workforce Development, and Department of Transportation staff convened in 2021, and the extensive community outreach mentioned above and listed partially at the following link:
https://www.oaklandca.gov/Government/Oakland-Improvement-Projects/Building-

Electrification/Building-Electrification-Public-Engagement.

The City also published public notice of this action in the Alameda Times-Star on September 5, 2025 and September 12, 2025 and the Oakland Tribune on September 12, 2025 in compliance with Government Code section 6066.

COORDINATION

The Sustainability and Resilience Division of the City Administrator’s Office, the Building Bureau of the Planning and Building Department, the Office of the City Attorney, the Department of Race and Equity, and the Budget Office have reviewed this report and proposed legislation.

SUSTAINABLE OPPORTUNITIES

Economic: These proposed amendments to the Model Construction Codes support housing and commercial development opportunities for new and remodeled building construction.

Cost-Effectiveness of High-Performance New Construction Multiple analyses have concluded that all-electric new construction is cost-effective, often resulting in lower upfront costs due to the avoidance of gas infrastructure, which can cost between $7,050 and $9,500 for a single-family home. The performance standards in this ordinance are designed to make all-electric construction the most economically advantageous compliance pathway for developers.

Cost-Effectiveness of Alteration Requirements
Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 8
City Council
September 15, 2025

Requiring electrification-readiness and efficiency upgrades during a significant remodel is the most cost-effective time to undertake such work. The marginal cost of adding a 240-volt circuit or upgrading an electrical panel is significantly lower when walls are already open and electricians are on-site for other work. The ordinance provides a flexible menu of options, allowing property owners to choose the most practical and affordable measures for their specific project, thereby avoiding undue financial burden while preparing the home for a fossil-fuel-free future.

Environmental: Natural gas, or methane, is a Short-Lived Climate Pollutant, with 86 times the global warming potential of carbon dioxide over a 20-year period. There is broad consensus among climate scientists that the world cannot limit global warming to 1.5 degrees Celsius without drastically limiting methane emissions, including from buildings. The reduction of greenhouse gas emissions by preparing buildings for future electrification that results in actual cost reductions will help mitigate climate change and its negative effects such as extreme heat events, droughts, intense storms, flooding, and displacement. This ordinance would fulfill Action B-1 in the 2030 ECAP, Eliminate Natural Gas in New Buildings, and prime the market for a smoother transition to full electrification for Oakland’s existing buildings—the subject of 2030 ECAP Action B-2, Plan for All Existing Buildings to be Efficient and All-Electric by 2040.

Race & Equity: Ensuring that new buildings are constructed without fossil fuel infrastructure and instead with local, carbon-free renewable energy sources will bring health and economic benefits to low-income communities. Modern electric systems and appliances are more efficient than older gas technologies, and in some cases offer lower overall installation costs and utility bills. They also offer improved air quality and less exposure to pollutants known to exacerbate asthma and other pulmonary diseases, which disproportionately impact vulnerable populations like children and seniors. Heat pumps add air conditioning capacity in areas with heat stress, and induction cooking is safer with lower exposure to hot surfaces and no open flames.

Eliminating natural gas in buildings can lower the risk of fire after earthquakes, and reduce the likelihood of childhood asthma. All of these benefits disproportionately improve wellbeing in frontline communities, who face higher baseline levels of pollution exposure and pay a higher proportion of income for energy. These recommendations are also in alignment with O.M.C.

2.29.17.B.10 which direct departments to support “housing for all people that is safe, affordable, high quality and healthy. “
While new construction standards are vital, according to Census data over 40% of Oakland's building stock was built before 1940. Older, poorer-quality housing is concentrated in EJ communities, and these homes are more likely to contain inefficient, polluting gas appliances.

The proposed amendment to the Energy Code and CALGreen addresses this directly by requiring upgrades during significant renovations. This ensures that as investment occurs, existing homes are made healthier by preparing them for the transition away from fossil fuels, directly improving indoor air quality and implementing ECAP Action B-2 and EJ Element Policy EJ-1.11.

CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA)

The Health and Safety Code Section 18941.5, with reference to Section 17958.7, allows more restrictive local amendments to the Building Code that are reasonably necessary due to local climatic, geologic, or topographical conditions. This ordinance is exempt from CEQA under Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 9
City Council
September 15, 2025

CEQA Guidelines sections15061(b)(3) and 15308 due to the fact it is a regulatory action for the protection of the environment and that there are no reasonably foreseeable adverse impacts that would result from this action. As a result, there is no possibility that the activity in question would have a significant effect on the environment.

ACTION REQUESTED OF THE CITY COUNCIL

The City Administration Recommends That, After Conducting A Public Hearing And Upon Conclusion, The City Council Adopt The Following Pieces Of Legislation:
(1) An Ordinance: (1) Adding Oakland Municipal Code (“O.M.C.”) Chapter 15.06, “Oakland Amendments to the California Energy and Green Building Codes,” Related To Building Decarbonization, Energy Efficiency, And Public Health To Meet the City of Oakland’s Resource Conservation and Climate Goals; (2) Repealing The City Of Oakland’s Local Amendments To The 2022 Edition Of The California Energy Code (Title 24, Part 6) And The 2022 California Green Building Code (Title 24, Part 11) at O.M.C. Chapter 15.04, Part 6 and Part 11 Administrative and Technical Amendments; And (3) Adopting Appropriate California Environmental Quality Act Findings; And

(2) A Resolution Of Findings Supporting The Adoption Of An Ordinance: (1) Adding Oakland Municipal Code (“O.M.C.”) Chapter 15.06, “Oakland Amendments to the California Energy and Green Building Codes” To O.M.C. Title 15, “Buildings and Construction;” (2) Repealing The City Of Oakland’s Local Amendments To The 2022 Edition Of The California Energy Code (Title 24, Part 6) And The 2022 California Green Building Code (Title 24, Part 11); And (3) Adopting Appropriate California Environmental Quality Act Exemption Findings.

For questions regarding this report, please contact: Cecilia Muela, Interim Deputy Director Building Bureau/Chief Building Official, 510-238-6315.

Respectfully submitted,

William Gilchrist (Sep 11, 2025 10:07:21 PDT)

WILLIAM A. GILCHRIST
Director, Planning and Building Department

Reviewed by:

Shayna Hirshfield-Gold, Acting Sustainability
Manager
Environmental Services
Division Public Works
Department
Jestin D. Johnson, City Administrator
Subject: Adoption of Local Amendments For Energy and Green Building Code Related to Decarbonization, Energy Efficiency, and Public Health
Date: September 8, 2025 Page 10
City Council
September 15, 2025

Jacque Larrainzar, Program Analyst III
Department of Race and Equity
Jing Wong, Supervising Civil Engineer
Bureau of Building
Planning & Building Department

Prepared by:

Rodolfo Dueñas, Acting Process
Improvement Manager
Bureau of Building
Planning & Building Department

Attachments:
1) Reach Codes 2019 Cost-effectiveness Study:

Low-Rise Residential New Construction
16 Title 24, Parts 6 and 11
Local Energy Efficiency Ordinances
2019 Cost-Effectiveness Study:

Existing Low-r ise Residential Building
Efficiency Upgrade
Prepared for:

Kelly Cunningham
Codes and Standards Program
Pacific Gas and Electric Company
Pr
epared by:

Frontier Energy, Inc.

Misti Bruceri & Associates, LLC
Last
Modified: December 19, 2019
Attachment 1

LEGAL NOTICE

This report was prepared by Pacific Gas and Electric Company and funded by the California utility customers under the auspices of the California Public Utilities Commission.

Neither PG&E nor any of its employees makes any warranty, express or implied; or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any data, information, method, product, policy or process disclosed in this document; or represents that its use will not infringe any privately-owned rights including, but not limited to, patents, trademarks or copyrights.

2019-12-19
Table of Contents
Acronyms .......................................................................................................................................................... 3 1 Overview ................................................................................................................................................... 4 2 Introduction ............................................................................................................................................... 4 3 Methodology and Assumptions ................................................................................................................. 5

3.1 Building Prototypes ......................................................................................................................................... 5

3.2 Efficiency Measures ....................................................................................................................................... 8

3.3 Efficiency Packages ....................................................................................................................................... 9

3.4 Measure Cost ................................................................................................................................................. 9

3.4.1 Cost-Effectiveness ................................................................................................................................... 11 4 Results .................................................................................................................................................... 12 5 Recommendations & Discussion ............................................................................................................ 16

5.1 Recommended Efficiency Measures ............................................................................................................ 16

5.2 Other Considerations .................................................................................................................................... 18

5.3 Next Steps .................................................................................................................................................... 18 6 References ............................................................................................................................................. 20 Appendix A – California Climate Zone Map .................................................................................................... 21 Appendix B – Utility Rate Tariffs ..................................................................................................................... 22 Appendix C – Standards Sections .................................................................................................................. 32

6.1.1 2019 Building Energy Efficiency Standards Section 150.2(b)1I ............................................................... 32

6.1.2 2019 Building Energy Efficiency Standards Section 150.2(b)1E .............................................................. 32

6.1.3 2019 Building Energy Efficiency Standards Section 110.9(b)4 ................................................................ 33 Appendix D – Measure Cost-effectiveness Tables ......................................................................................... 34

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List of Tables
Table 1: Prototype Characteristics ................................................................................................................................... 6 Table 2: Efficiency Characteristics for Three Vintage Cases ........................................................................................... 7 Table 3: Measure Descriptions & Cost Assumptions1 .................................................................................................... 10 Table 4: IOU Utility Tariffs Applied Based on Climate Zone ........................................................................................... 11 Table 5: Final Financing Assumptions ........................................................................................................................... 12 Table 6: Summary of Single Family Results .................................................................................................................. 14 Table 7: Summary of Multifamily Results ....................................................................................................................... 15 Table 8: PG&E Baseline Territory by Climate Zone ...................................................................................................... 23 Table 9: SCE Baseline Territory by Climate Zone ......................................................................................................... 26 Table 10: SoCalGas Baseline Territory by Climate Zone .............................................................................................. 28 Table 11: SDG&E Baseline Territory by Climate Zone ................................................................................................. 29 Table 12: Real Utility Rate Escalation Rate Assumptions .............................................................................................. 31 Table 13: CZ 1 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 34 Table 14: CZ 1 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 34 Table 15: CZ 2 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 35 Table 16: CZ 2 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 35 Table 17: CZ 3 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 36 Table 18: CZ 3 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 36 Table 19: CZ 4 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 37 Table 20: CZ 4 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 37 Table 21: CZ 5 PG&E/PG&E - Single Family Efficiency Upgrade Cost-effectiveness Results ...................................... 38 Table 22: CZ 5 PG&E/PG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit)........................... 38 Table 23: CZ 5 PG&E/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results ................................ 39 Table 24: CZ 5 PG&E/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .................... 39 Table 25: CZ 6 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 40 Table 26: CZ 6 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 40 T
able 27: CZ 7 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 41 Table 28: CZ 7 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 41 Table 29: CZ 8 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 42 Table 30: CZ 8 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 42 Table 31: CZ 9 - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................................ 43 Table 32: CZ 9 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................................ 43 Table 33: CZ 10 SCE/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results................................. 44 Table 34: CZ 10 SCE/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ..................... 44 Table 35: CZ 10 SDG&E - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................. 45 Table 36: CZ 10 SDG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................. 45 Table 37: CZ 11 - Single Family Efficiency Upgrade Cost-effectiveness Results .......................................................... 46 Table 38: CZ 11 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .............................................. 46 Table 39: CZ 12 - Single Family Efficiency Upgrade Cost-effectiveness Results .......................................................... 47 Table 40: CZ 12 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .............................................. 47 Table 41: CZ 13 - Single Family Efficiency Upgrade Cost-effectiveness Results .......................................................... 48 Table 42: CZ 13 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .............................................. 48 Table 43: CZ 14 SCE/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results................................. 49 Table 44: CZ 14 SCE/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ..................... 49 Table 45: CZ 14 SDG&E - Single Family Efficiency Upgrade Cost-effectiveness Results ............................................. 50 Table 46: CZ 14 SDG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) ................................. 50 Table 47: CZ 15 - Single Family Efficiency Upgrade Cost-effectiveness Results .......................................................... 51 Table 48: CZ 15 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .............................................. 51 Table 49: CZ 16 - Single Family Efficiency Upgrade Cost-effectiveness Results .......................................................... 52

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Table 50: CZ 16 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) .............................................. 52

Acronyms

ACH50 Air Changes per Hour at 50 pascals pressure differential ACM Alternative Calculation Method
AFUE Annual Fuel Utilization Efficiency
B/C Lifecycle Benefit-to-Cost Ratio
BEopt Building Energy Optimization Tool
BSC Building Standards Commission
CBECC-Res Computer program developed by the California Energy Commission for use in demonstrating compliance with the California Residential Building Energy Efficiency Standards CFI California Flexible Installation
CZ California Climate Zone
EDR Energy Design Rating
EER Energy Efficiency Ratio
HERS Rater Home Energy Rating System Rater
HVAC Heating, Ventilation, and Air Conditioning
IOU Investor Owned Utility
kWh Kilowatt Hour
MF Multifamily
NPV Net Present Value
PG&E Pacific Gas and Electric Company
SCE Southern California Edison
SDG&E San Diego Gas and Electric
SEER Seasonal Energy Efficiency Ratio
SF Single Family
CASE Codes and Standards Enhancement
TDV Time Dependent Valuation
Title 24 Title 24, Part 6
TOU Time-Of-Use
Existing Building Efficiency Upgrade Cost-effectiveness Study

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1 Overview
The California Codes and Standards Reach Codes team has completed a preliminary cost-effectiveness study for existing building upgrades. This analysis evaluated the feasibility and cost-effectiveness of retrofit measures in California existing homes built before 2006. A customer-based lifecycle cost approach to evaluating cost- effectiveness was applied quantifying the utility cost savings associated with energy efficiency measures compared to the costs associated with the measures. This preliminary study updated a cost-effectiveness study completed in June 2018 (Statewide Reach Codes Team, 2018). The focus of this study was to revisit the recommended retrofit efficiency measure and package cost-effectiveness based on current utility rates and updated measure costs. Additional efforts have been identified that will be evaluated and released in an updated Existing Building Efficiency Upgrade Cost-Effectiveness Study in 2020. These include:
• Revisit base case assumptions for different vintages
• Additional HVAC upgrade options including:
o High efficiency equipment replacement as alternative to non-preempted upgrade o Air sealing and attic insulation at time of HVAC replacement o Improved duct insulation, tighter ducts, buried ducts • Additional building envelope improvements
o Higher ceiling insulation requirements
o Address low-slope roof replacements
• Lighting luminaire replacements in addition to lamp replacements • Evaluation of electrification measures at equipment change-out and electrification-ready • Additions: Installation of PV system when building an addition, and • PV System Installation: Additional efficiency upgrade requirements when installing PV 2 Introduction
The California Building Energy Efficiency Standards Title 24, Part 6 (Title 24) (Energy Commission, 2018b) is maintained and updated every three years by two state agencies, the California Energy Commission (Energy Commission) and the Building Standards Commission (BSC). In addition to enforcing the code, local jurisdictions have the authority to adopt local energy efficiency ordinances, or reach codes, that exceed the minimum standards defined by Title 24 (as established by Public Resources Code Section 25402.1(h)2 and Section 10-106 of the Building Energy Efficiency Standards). Local jurisdictions must demonstrate that the requirements of the proposed ordinance are cost-effective and do not result in buildings consuming more energy than is permitted by Title 24. In addition, the jurisdiction must obtain approval from the Energy Commission and file the ordinance with the BSC for the ordinance to be legally enforceable.

This report documents cost-effective combinations of measures that exceed the minimum state requirements, the 2019 Building Energy Efficiency Standards, effective January 1, 2020, for existing single family and low-rise (one- to three-habitable story) multifamily buildings when a remodel is submitted for permit. This analysis does not apply to high-rise multifamily buildings (four habitable stories or greater), nor to common areas categorized as nonresidential spaces within low-rise multifamily buildings. Each jurisdiction must establish the appropriate threshold for triggering the requirements, often based on the value of the project or percent of floor area impacted. Alternatively, a jurisdiction could require the upgrades described in this analysis at the time of sale or listing of a home. The analysis includes scenarios of individual measures, as well as package upgrades, and identifies cost-effective options based on the existing conditions of the building in all sixteen California Climate Zones (CZ) (see Appendix A – California Climate Zone Map for a graphical depiction of Climate Zone locations).

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This analysis does not evaluate the impact of retrofit measures on Title 24 compliance margins, as the proposed measures are required in addition to achieving compliance with all codes. The analysis uses a customer-based lifecycle cost approach for evaluating cost-effectiveness of the proposed upgrades, which requires estimating and quantifying incremental costs and the energy and utility cost savings for each energy efficiency measure.

The applied approach establishes recommendations based on existing conditions and cost-effectiveness of each measure or package.
3 Methodology and Assumptions
The general approach applied in this analysis is to evaluate performance and determine cost-effectiveness of various energy retrofit measures, individually and as packages. Both single family and low-rise multifamily cases are considered, for three unique building vintages: pre-1978, 1978-1991, and 1992-2005. The vintages were defined based on review of historic Title 24 code requirements and selecting year ranges with distinguishing features.

The California Building Energy Code Compliance – Residential (CBECC-Res) 2016.3.0 (SP2 977) compliance simulation tool was used to evaluate energy savings for most measures, with the exception of those outside the code compliance scope. In these cases, the National Renewable Energy Laboratory’s Building Energy Optimization (BEopt) v2.8 software and the EnergyPlus v8.8 simulation engine were used.

This analysis builds on the work completed for the 2016 Title 24 code (Statewide Reach Codes Team, 2018) and has been updated to reflect changes in measure costs over time as well as current utility tariffs. Energy simulations were not re-evaluated in CBECC-Res 2019 because there have been minimal updates to the software that impact the energy use results. This was validated by evaluating the pre-1978 basecase model in climate zone 12 with the version of the CBECC-Res software for the 2019 code, and comparing annual energy use with that from the 2016 version of software. Both total electricity and natural gas use differed between the two version by less than one percent. Therefore, this analysis can support ordinances adopted under either the 2016 or 2019 Title 24 code.

3.1 Building Prototypes
The Energy Commission defines building prototypes which it uses to evaluate the cost-effectiveness of proposed changes to Title 24 requirements. For the multifamily analysis, the Energy Commission eight-unit, two-story, multifamily new construction prototype was determined to be representative of low-rise multifamily buildings across the state within the vintages evaluated under this analysis. A single two-bedroom unit was extracted from the multifamily building model because CBECC-Res cannot evaluate building envelope air sealing for multifamily buildings. The two-bedroom unit was modified to be orientation neutral and represent the average properties of a lower floor and upper floor unit. Only individual, in-unit water heating and space conditioning systems were evaluated. Additional details on the multifamily prototype can be found in the Alternative Calculation Method (ACM) Approval Manual (Energy Commission, 2018a).

Average home size has steadily increased over time,1 and the Energy Commission single family new construction prototypes are larger than many existing single family homes across California. For this analysis an existing home

1 https://www.census.gov/const/C25Ann/sftotalmedavgsqft.pdf Existing Building Efficiency Upgrade Cost-effectiveness Study

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model developed by the Energy Commission for residential ACM testing2 was used with the following revisions.

The original model includes an existing 1,440 square foot space and a 225 square foot addition. For this analysis, the entire 1,665 square feet was evaluated as existing space and features (i.e., insulation levels, glazing) were applied consistently across the entire building consistent with the existing home specifications in Table 2.

Additions are not addressed in this analysis as they are already addressed by the Title 24, Part 6 code.

Table 1 describes the basic characteristics of each prototype.

Table 1: Prototype Characteristics
Single Family Multifamily
Existing Conditioned Floor Area 1,665 ft2 960 ft2 unit
Num. of Stories 1 1
Num. of Bedrooms 3 2
Window-to-Floor Area Ratio 13% 15%

Three building vintages were evaluated to determine sensitivity of existing building performance on cost- effectiveness of upgrades. For example, it is widely recognized that adding attic insulation in an older home with no insulation is cost-effective, however, newer homes will likely have at least some existing insulation in the attic reducing the potential savings from the measure. The building characteristics for each vintage were determined based on either prescriptive requirements from the Title 24 code that was in effect or standard construction practice during that time period. Based on the vintages selected, this analysis covers homes built before 2006. Homes built between 2006 and 2012 are expected to be similar in envelope characteristics to the 1992-2005 era homes, but include higher performing HVAC.

Table 2 summarizes the assumptions for each of the three vintages. Additionally, the analysis assumed the following features when modeling the prototype buildings:
• Individual space conditioning and water heating systems, one per apartment or single family building.

Multifamily buildings with central HVAC or water heating systems were not considered in this evaluation.
• Split-system air conditioner with gas furnace. Efficiency defined by year of the most recent equipment replacement (based on standard equipment lifetime).
• Small storage gas water heater. Efficiency defined by year of most recent equipment replacement (based on standard equipment lifetime).
• Gas cooktop, oven, and clothes dryer.

2 Residential ACM test U12 can be accessed at the following website:
http://www.bwilcox.com/BEES/cbecc2016.html
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Table 2: Efficiency Characteristics for Three Vintage Cases Building Component Efficiency
Feature
Vintage Case
Pre-1978 1978-1991 1992-2005
Envelope
Exterior Walls 2x4 16"oc wood frame, R-0 2x4 16"oc wood frame, R-11 2x4 16"oc wood frame, R-13 Foundation Type & Insulation Raised floor, R-0 Uninsulated slab (CZ 2-15) Raised floor, R-0 (CZ 1 & 16)
Uninsulated slab (CZ 1-15)
Raised floor, R-19 (CZ 16)
Ceiling Insulation & Attic Type
Vented attic, R-11 @ ceiling level
Vented attic, R-5 @ ceiling level (CZ 6
& 7)
Vented attic, R-19 @ ceiling level Vented attic, R-19 @ ceiling level Roofing Material & Color Asphalt shingles, dark Asphalt shingles, dark Asphalt shingles, dark Radiant Barrier No No No
Window Type: U-factor / SHGC1 Metal, single pane: 1.16 / 0.76 Metal, dual pane: 0.79 / 0.70 Vinyl, dual pane Low-E: 0.55 / 0.40 House Infiltration 10 ACH50 10 ACH50 7 ACH50
HVAC Equipment2
Heating Efficiency 78 AFUE (assumes 1 replacement) 78 AFUE (assumes 1 replacement) 78 AFUE Cooling Efficiency 9.7 SEER (assumes 1 replacement) 9.7 SEER (assumes 1 replacement) 9.7 SEER Duct Location & Details Attic, R-2.1, 30% leakage Attic, R-2.1, 25% leakage Attic, R-4.2, 25% leakage Whole Building Mechanical Ventilation None None None
Water Heating Equipment2
Water Heater Efficiency 0.575 Energy Factor (assumes 2
replacements)

0.575 Energy Factor (assumes 1
replacement) 0.575 Energy Factor
Water Heater Tank 40gal uninsulated tank 40gal uninsulated tank 40gal uninsulated tank Pipe Insulation None None None
Hot Water Fixtures Standard, non-low flow Standard, non-low flow Standard, non-low flow 1 Window type selections were made based on conversations with window industry expert , Ken Nittler. If a technology was entering the market during the time period (e.g. Low-E during 1992-2005 or dual pane during 1978-1991) that technology was included in the analysis. This provides a conservative assumption for overall building performance and additional measures may be cost effective for buildings with lower performing windows, for example buildings with metal single pane windows in the 1978-1991 vintage.
2Multifamily analysis assumes one HVAC and water heating system per apartment.

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3.2 Efficiency Measures
The methodology used in the analyses for each of the prototypical building types begins with a design that matches the specifications as described in Table 2 for each of the three vintages. Prospective energy efficiency measures were modeled in each of the prototypes to determine the projected electricity and natural gas energy savings relative to the baseline vintage. In some cases, where logical, measures were packaged together. Unless specified otherwise, all measures were evaluated using CBECC-Res.

All measures are evaluated based on work required above and beyond any work triggered by Title 24 code requirements. Measures apply regardless of the scope of the remodel and are evaluated assuming they are not otherwise required by Title 24. For example, duct sealing is required by code whenever heating and cooling equipment is altered. For this analysis duct sealing was evaluated for those projects where it is not already triggered by code (i.e., no changes to the heating or cooling equipment). Where appropriate, measure requirements align with those defined in Title 24. The one exception is the cool roof measure which applies when a building is already installing a new roof as part of the remodel. The minimum solar reflectance value is more stringent than that required in Title 24, Part 6.

Following are descriptions of each of the efficiency upgrade measures applied in this analysis.

Attic Insulation: Add attic insulation in buildings with vented attic spaces to meet R-38.

Air Sealing & Weather-stripping: Apply air sealing practices throughout all accessible areas of the building. For this study, it was assumed that older vintage buildings would be leakier than newer buildings and that approximately 30% improvement in air leakage was achievable through air sealing of all accessible areas. For modeling purposes, it was assumed that air sealing can reduce infiltration levels from 10 to 7 air changes per hour at 50 Pascals pressure difference (ACH50) in the two older vintages (pre-1992) and from 7 to 5 ACH50 in the newer vintage.

Cool Roof: For steep slope roofs, install a roofing product rated by the Cool Roof Rating Council (CRRC) with an aged solar reflectance of 0.25 or higher and thermal emittance of 0.75 or higher. This measure only applies to buildings that are installing a new roof as part of the scope of the remodel; the cost and energy savings associated with this upgrade reflects the incremental step between a standard roofing product with one that is CRRC rated with an aged solar reflectance of 0.25. This is similar to cool roof requirements in 2019 Title 24 Section 150.2(b)1Ii but assumes a higher solar reflectance.

Window Replacement: Replace existing single pane windows with a dual pane product, which has a U-factor equal to 0.32 or lower and a Solar Heat Gain Coefficient (SHGC) equal to 0.25 or lower. This measure was only evaluated for the pre-1978 vintage, which is assumed to have single-pane, metal-frame windows.

Duct Sealing: Air seal all ductwork to meet the requirements of the 2019 Title 24 Section 150.2(b)1E. For this analysis, a final duct leakage value of 15 percent was applied, which corresponds to Option i in the Title 24 code section referenced.

Water Heater Blanket: Add R-6 insulation to the exterior of existing residential tank storage water heaters. For the analysis, the water heater was modeled within conditioned space, which is a typical configuration for older homes. This assumption is conservative since a water heater located in unconditioned space will tend to have higher tank losses and installing a water heater blanket in those situations will result in additional savings. The energy savings for this measure reflect only water heating energy savings only, and do not include any impacts to the space conditioning load, which reduces space cooling loads and increases space heating loads. The impact on space conditioning energy used would be minimal. In most climates, with the exception of heating dominated ones, the combination of these two impacts results in net energy savings. This measure was Existing Building Efficiency Upgrade Cost-effectiveness Study 9 2019-12-19

evaluated using EnergyPlus. This measure was evaluated for individual water heaters only and would not apply to central water heating systems.

Hot Water Pipe Insulation: Insulate all accessible hot water pipes with R-3 pipe insulation. In certain buildings which have slab on grade construction, and the majority of pipes located either underground or within the walls, most of the pipes will be inaccessible. For the purposes of this analysis a conservative assumption that only ten percent of the pipes could be insulated was applied. In buildings where pipes are located in the attic, crawlspace, or are otherwise more accessible, energy savings will be higher than those presented in this analysis. This measure was evaluated using BEopt and EnergyPlus.

Low Flow Fixtures: Upgrade sink and shower fittings to meet current CALGreen requirements, which require maximum flow rates of 1.8 gallons per minute (gpm) for showerheads and kitchen faucets, and 1.2 gpm for bathroom faucets. Baseline whole house hot water use was based on BEopt assumptions and this measure assumed the upgraded fixtures reduce flow rates by ten percent for showerheads and 20 percent for all faucets based on a 2010 water use study (ConSol, 2010). This measure was evaluated using BEopt and EnergyPlus.

LED Lighting: Replace screw-in incandescent lamps and compact fluorescent lamps (CFLs) with screw-in light emitting diode (LED) lamps. This analysis was conducted external to the energy model and evaluated replacement of both a single 45 W incandescent lamp and a 13W CFL lamp with an 11 W LED lamp operating 620 hours annually. Annual hour estimates were based on whole building average hours of operation from a 2010 lighting study by KEMA (KEMA, 2010). Lifetime assumptions were 1,000 hours for incandescent lamps, 10,000 hours for CFLs and 25,000 hours for LED lamps.

Lighting Vacancy Sensors: Install manual on - automatic off vacancy sensors that meet the requirements of Title 24 Section 110.9(b)4. This analysis was conducted external to the energy model, assuming ten percent savings in operating hours for a single vacancy sensor installed on a switch controlling three lamps. Energy savings were calculated assuming both 45 W incandescent lamps and 11 W LED lamps, operating 620 hours annually. Annual hour estimates were based on whole building average hours of operation from a 2010 lighting study by KEMA (KEMA, 2010).

3.3 Efficiency Packages
A few of the measures described above were also evaluated as part of a package. Three packages were developed as described below.

Envelope & Duct Package – R-38 Attic Insulation & Air Sealing & Duct Sealing: Air sealing and attic insulation are very often applied as a package in building retrofits. The boundary between the living space and vented attics is where a significant amount of building air leakage can occur and sealing these areas as well as ducts prior to covering the attic floor with insulation is both practical and effective. Air sealing, duct sealing and insulation also directly address occupant comfort, as they reduce heat transfer, and result in more even temperatures within the building.

Water Heating Package – Water Heater Blanket, Hot Water Pipe Insulation, & Low-Flow Fixtures: These three water heating measures are all relatively low cost and work together to reduce building hot water energy use.

3.4 Measure Cost
Table 3 summarizes the cost assumptions for each of the measures evaluated. Costs were obtained from various sources, including local contractors, internet searches, past projects, and technical reports.

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Table 3: Measure Descriptions & Cost Assumptions1
Measure Performance
Level
Incremental Cost –
Single Family Building
Incremental Cost -
Multifamily Residential Unit
Source Notes
(SF = single family; MF = multifamily) Pre
1978
1978 –
1991
1992 -
2005
Pre
1978
1978 –
1991
1992 -
2005
Attic Insulation R-38 $1,915 $1,548 $1,548 $500 $405 $405 Retrofit contractor2
$1.37/sqft ceiling area to add insulation to existing R-11 insulation
$1.21/sqft to add insulation to existing R-19 insulation Air sealing 7 ACH50 $959 $959 n/a $341 $341 n/a Retrofit contractor2
$173 materials & 19.5 hours labor ($40.30/hr common labor rate)5 for SF. $67 materials and 6.8 hours labor for MF. 5 ACH50 n/a n/a $959 n/a n/a $341 Cool roof
Aged
Reflectance
> 0.25
$577 $577 $577 $167 $167 $167 Research
report3
Based on $0.32/sqft roof area incremental cost for cool asphalt shingle product, plus a 10% contractor markup. Higher
reflectance values for lower cost are achievable for tile roof products
Window U-factor/
SHGC 0.32/0.25 $9,810 n/a n/a $5,873 n/a n/a Retrofit
contractor4 Based on $45/sqft window area installed cost Duct sealing
15% of
nominal
airflow
$240 $240 $240 $120 $120 $120 HVAC
contractor
Assumes 4 hours of labor for SF and 2 hours per MF apartment with ducts in the attic ($54/hr HVAC labor rate)5 + $24 material for SF and $12 material for MF (per unit).

Water heater
blanket R-6 $40 $40 $40 $40 $40 $40 Internet
search $20 blanket + ½-hr labor ($40.30/hr laborer rate)5 Hot water pipe
insulation 3/4” (R-3) $42 $42 $42 $42 $42 $42 Internet
search
$0.20/ft of ¾” pipe insulation. 10ft total + 1-hr labor ($40.30/hr common labor rate)5
Low flow fixtures CALGreen $126 $126 $126 $86 $86 $86 Retrofit contractor4
Showerheads at $34.74 each + sink aerators at $5.37 each + 1- hr labor ($40.30/hr common labor rate)5. 2 showerheads & 3 aerators assumed for SF and 1 showerhead and 2 aerators for MF.

LED lamp 11W screw-in
bulb $4 $4 $4 $4 $4 $4 Internet
search
$4 for LED dimmable A19 lamp 60W equivalent. $0.97 for an equivalent incandescent product which was used to estimate total replacement costs. Cost based on a single lamp
replacement
Vacancy Sensor Manual on,
auto off $30 $30 $30 $30 $30 $30 Internet
search $20 per sensor + 1/4-hr labor ($40.30/hr common labor rate)5. 1 Costs include contractor overhead and profit
2 Source: Retrofit contractor pricing, including labor, obtained by Davis Energy Group through the 2012 LA County Retrofit Program (DEG, 2017). 3 Codes and Standards Enhancement Initiative: Residential Roof Envelope Measures. 2013 Title 24. http://www.energy.ca.gov/title24/2013standards/prerulemaking/documents/current/Reports/Residential/Envelope/2013_CASE_R_Roof_ Measures_Oct_2011.pdf 4 Source: Retrofit contractor pricing obtained by Davis Energy Group through the Stockton Energy Challenge neighborhood retrofit program (DEG, 2017). 5 Labor rates are estimated from RSMeans (RSMeans, 2014).

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3.4.1 Cost-Effectiveness
A customer-based approach to evaluating cost-effectiveness was used based on experience with reach code adoption by local governments. Residential utility rates at the time of the analysis were applied to calculate utility costs for all cases and determine cost-effectiveness for the proposed measures and packages. First year utility costs were calculated using hourly electricity and gas output from CBECC-Res and applying the utility tariffs summarized in Table 4. The applicable residential time-of-use (TOU) rate was applied to all cases.

Climate zones have been applied according to the predominant investor owned utility (IOU) serving the population of each zone. Climate Zones 10 and 14 are evaluated with both SCE/SoCalGas and SDG&E tariffs since each utility has customers within these climate zones. Climate Zone 5 is evaluated under both PG&E and SoCalGas natural gas rates.

Table 4: IOU Utility Tariffs Applied Based on Climate Zone Climate Zones Electric/Gas
Utility
Electricity
(Standard)
Natural
Gas
1-5, 11-13, 16 PG&E E-TOU,
Option B
G1
5 PG&E /
SoCalGas
E-TOU,
Option B
GR
6, 8-10, 14, 15 SCE/SoCalGas TOU-D-4-9 GR
7, 10, 14 SDG&E D TOU-DR1 GR
Source: Utility websites, see Appendix B – Utility Rate Tariffs for details on the tariffs applied.

Utility rates are assumed to escalate over time, using assumptions from research conducted by Energy and Environmental Economics (E3) in the 2019 study Residential Building Electrification in California study (Energy & Environmental Economics, 2019). Escalation of natural gas rates between 2019 and 2022 is based on the currently filed General Rate Cases (GRCs) for PG&E, SoCalGas and SDG&E. From 2023 through 2025, gas rates are assumed to escalate at 4% per year above inflation, which reflects historical rate increases between 2013 and 2018. Escalation of electricity rates from 2019 through 2025 is assumed to be 2% per year above inflation, based on electric utility estimates. After 2025, escalation rates for both natural gas and electric rates are assumed to drop to a more conservative 1% escalation per year above inflation for long-term rate trajectories beginning in 2026 through 2050. See Appendix B – Utility Rate Tariffs for additional details.

Cost-effectiveness was evaluated for all 16 climate zones and results are presented as a lifecycle benefit-to-cost (B/C) ratio, a net present value (NPV) metric which represents the cost-effectiveness of a measure over a 30- year lifetime taking into account discounting of future savings and costs and financing of incremental first costs.

A value of one indicates the NPV of the savings over the life of the measure is equivalent to the NPV of the lifetime incremental cost of that measure. A value greater than one represents a positive return on investment.

The B/C ratio is calculated according to Equation 1.

Equation 1
𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵 − 𝐵𝐵𝑡𝑡 − 𝐶𝐶𝑡𝑡𝐶𝐶𝐵𝐵 𝑅𝑅𝑅𝑅𝐵𝐵𝐵𝐵𝑡𝑡 = 𝑁𝑁𝑁𝑁𝑁𝑁 𝑡𝑡𝐵𝐵 𝑙𝑙𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝑙𝑙𝐵𝐵 𝑏𝑏𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵 𝑁𝑁𝑁𝑁𝑁𝑁 𝑡𝑡𝐵𝐵 𝑙𝑙𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝑙𝑙𝐵𝐵 𝑐𝑐𝑡𝑡𝐶𝐶𝐵𝐵
The benefit is represented by annual utility savings and the cost by incremental first cost and replacement costs.

The lifetime costs or benefits are calculated according to Equation 2.

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Equation 2
𝑵𝑵𝑵𝑵𝑵𝑵 𝒐𝒐𝒐𝒐 𝒍𝒍𝒍𝒍𝒐𝒐𝒍𝒍𝒍𝒍𝒍𝒍𝒍𝒍𝒍𝒍 𝒄𝒄𝒐𝒐𝒄𝒄𝒍𝒍 𝒐𝒐𝒐𝒐 𝒃𝒃𝒍𝒍𝒃𝒃𝒍𝒍𝒐𝒐𝒍𝒍𝒍𝒍 = ∑ (𝑨𝑨𝒃𝒃𝒃𝒃𝑨𝑨𝑨𝑨𝒍𝒍 𝒄𝒄𝒐𝒐𝒄𝒄𝒍𝒍 𝒐𝒐𝒐𝒐 𝒃𝒃𝒍𝒍𝒃𝒃𝒍𝒍𝒐𝒐𝒍𝒍𝒍𝒍)𝒍𝒍 (𝟏𝟏+𝒐𝒐)𝒍𝒍
𝒃𝒃
𝒍𝒍=𝟎𝟎
Where:
• n = analysis term
• r = discount rate
The following summarizes the assumptions applied in this analysis to both methodologies. • Analysis term of 30-years
• Real discount rate of 3 percent
• First incremental costs are financed into a mortgage or loan

Table 5 summarizes the financing assumptions and terms that were applied in this analysis. The analysis term is 30 years in all cases. The LED lighting and vacancy sensor upgrades are the only measures that are not assumed to be financed.

Table 5: Final Financing Assumptions
Loan
Term
Loan
Rate
Single Family 30 5%
Multifamily 10 4%

Simple payback is also presented and is calculated using the equation below.

Simple payback = First incremental cost / First year utility cost savings Equation 3

Maintenance costs were not included for any measures because there are no incremental maintenance costs expected for any of the measures evaluated. Any maintenance requirements that would apply are similar to both the upgrade and the base case. LED lamp upgrade is the only measure with assumed replacement costs based on lifetime assumptions of LED and incandescent technologies and estimated operating hours. See the measures description in Section 2.2 for additional details. 4 Results
Cost-effectiveness analysis was completed for the three vintages and both single family and multifamily unit prototypes. Evaluations looked to identify cost-effective energy upgrades for existing buildings at the time of a remodel. Results are summarized below as well as in Table 6 for single family and Table 7 for multifamily.

Results of cost-effectiveness analysis along with energy savings are presented in Appendix D – Measure Cost- effectiveness Tables in Table 13 through Table 50 for single family and multifamily buildings, by climate zone.

Site energy savings, cost savings, measure cost, and cost-effectiveness including simple payback and lifecycle B/C ratio are provided. Results are presented for each of the three vintages. Shaded rows in the tables indicate that the measure is not cost-effective. The lifecycle B/C ratio threshold of one for the financed measures is roughly equivalent to a simple payback of 20 years for single family and 24 years for multifamily. For Climate Zones 10 and 14, cost-effectiveness results are separated out for buildings in both SCE and SDG&E territories, which differ based on applicable utility rates.

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Some measure results do not differ between the vintages such as LED lamp replacement and water heating upgrades. The water heating and LED lighting measures are cost-effective for both single family and multifamily in all cases. Cost-effectiveness for the envelope and sealing measures is dependent on climate zone and building vintage. A summary of these results is provided below.

Envelope & Duct Package – R-38 Attic Insulation & Air Sealing & Duct Sealing: All three of these measures are cost-effective for all vintages in inland, cooling climates, as well as cold climates (Climate Zone 1, and 9-16 for single family and Climate Zone 1, 2, 4, and 8-16 for multifamily).

Duct sealing is cost-effective in all cases except for single family homes in Climate Zone 6 built after 1991 and Climate Zone 7 built after 1977; and multifamily in Climate Zone 5 PG&E territory and Climate Zone 7 built after 1991.

Air sealing and attic insulation are less cost-effective in newer vintages in transitional and coastal climates. This package of measures is cost-effective in the following cases:
• Buildings built between 1992 and 2005: Single family Climate Zones 1 and 9-16; and multifamily Climate Zones 1, 2, 4, and 8-16.
• Buildings built between 1978 and 1991: Single family Climate Zones 1, 4 and 8-16; and multifamily Climate Zones 1, 2, 4 and 8-16.
• Buildings built before 1978: Single family and multifamily in Climate Zones 1-16.

Cost-effectiveness of the envelope and duct measures was better in SDG&E territory than SCE territory for both Climate Zone 10 and 14.

Cool Roof: Cool roof is cost-effective for all vintages of single family homes in Climate Zones 8 through 15 and multifamily homes in Climate Zones 2, 4, and 6 through 16. It is also cost-effective for homes built before 1978 for single family in Climate Zone 2, 4, 6, and 7 and for multifamily buildings in Climate Zone 5.

Window Replacement: Window replacements are only cost-effective in buildings built before 1978 in single family homes in Climate Zones 10 in SDG&E territory only and 13 through 15; and in multifamily homes in Climate Zones 5 in PG&E territory only, 10 in SDG&E territory only, and 11-16.

Water Heating Package – Water Heater Blanket, Hot Water Pipe Insulation, & Low-Flow Fixtures: The package including these three water heating measures is cost-effective in all climate zones.

Lighting – LED Lamps: Replacing either an existing CFL or incandescent lamp with an LED lamp is cost-effective in all climate zones. The lighting results in Appendix D report cost-effectiveness for replacement of CLFs with LED lamps. Replacement of incandescent with LED lamps result in simple paybacks of less than one year. While vacancy sensors are cost-effective when incandescent lamps are assumed, once lamps are replaced with LED luminaires, most of the savings disappear and vacancy sensors are not cost-effective. In 2020, industry standard practice will be 45 lumens per Watt or greater for all lamps, which make the vacancy sensor measure not cost- effective.

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Table 6: Summary of Single Family Results
CASE CZ1-
PGE
CZ2-
PGE
CZ3-
PGE
CZ4-
PGE
CZ5-
PGE
CZ5-
SCG
CZ6-
SCE
CZ7-
SDGE
CZ8-
SCE
CZ9-
SCE
CZ10-
SCE
CZ10-
SDGE
CZ11-
PGE
CZ12-
PGE
CZ13-
PGE
CZ14-
SCE
CZ14-
SDGE
CZ15-
SCE
CZ16-
PGE
Envelope
& Duct
Package
Pre-
1978
Ducts1/
R-382/
Air Seal3
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts Ducts Ducts
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
1978-
1991
Ducts/
R-38/
Air Seal
Ducts Ducts Ducts Ducts Ducts N/A N/A Ducts
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
1992-
2005 Ducts Ducts Ducts Ducts Ducts Ducts N/A N/A Ducts Ducts Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Cool
Roof
Pre-
1978 N/A Yes N/A Yes N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes N/A 1978-
1991 N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes N/A 1992-
2005 N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes N/A Windows Pre-
1978 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes N/A Yes N/A Yes Yes N/A Water
Heating
Package
All
Vintages Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes LED
Lamps
All
Vintages Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 1 Ducts refers to the Duct Sealing upgrade, which calls for the air seal of all ductwork to meet the requirements of the 2019 Title 24 Section 150.2(b)1E . 2 R-38 refers to the Attic Insulation upgrade, which calls for t he addition of attic insulation to a minimum level of R-38 in vented attics. 3 Air Seal refers to the Air Sealing upgrade, which calls for the sealing of all accessible cracks, holes and gaps in the building envelope at walls, floors, and ceilings.

Existing Building Efficiency Upgrade Cost-effectiveness Study 15 2019-12-19

Table 7: Summary of Multifamily Results
CASE CZ1-
PGE
CZ2-
PGE
CZ3-
PGE
CZ4-
PGE
CZ5-
PGE
CZ5-
SCG
CZ6-
SCE
CZ7-
SDGE
CZ8-
SCE
CZ9-
SCE
CZ10-
SCE
CZ10-
SDGE
CZ11-
PGE
CZ12-
PGE
CZ13-
PGE
CZ14-
SCE
CZ14-
SDGE
CZ15-
SCE
CZ16-
PGE
Envelope
& Duct
Package
Pre-
1978
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts Ducts/
R-38/
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
1978-
1991
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts
Ducts/
R-38/
Air Seal
Ducts Ducts Ducts Ducts
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
1992-
2005
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts Ducts N/A N/A N/A N/A Ducts
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Ducts/
R-38/
Air Seal
Cool
Roof
Pre-
1978 N/A Yes N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 1978-
1991 N/A Yes N/A Yes N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 1992-
2005 N/A Yes N/A Yes N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Windows Pre-
1978 N/A N/A N/A N/A Yes N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes Water
Heating
Package
All
Vintages Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes LED
Lamps
All
Vintages Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 1 Ducts refers to the Duct Sealing upgrade, which calls for the air seal of all ductwork to meet the requirements of the 2019 Title 24 Section 150.2(b)1E . 2 R-38 refers to the Attic Insulation upgrade, which calls for t he addition of attic insulation to a minimum level of R-38 in vented attics. 3 Air Seal refers to the Air Sealing upgrade, which calls for the sealing of all accessible cracks, holes and gaps in the building envelope at walls, floors, and ceilings.

Existing Building Efficiency Upgrade Cost-effectiveness Study 16 2019-12-19

5 Recommendations & Discussion
This analysis evaluated the feasibility and cost-effectiveness of retrofit measures in California existing homes built before 2006. A customer-based lifecycle cost approach to evaluating cost-effectiveness was applied quantifying the utility cost savings associated with energy efficiency measures compared to the costs associated with the measures.

5.1 Recommended Efficiency Measures
Based on the analysis, the following cost-effective measures or packages of measures are recommended. The multifamily measures apply only to residential spaces in low-rise buildings (3 stories or fewer) and not to any common or non-residential spaces. Descriptions of each measure or package are provided below. In most cases, exceptions are defined which would exempt a particular project from a measure if certain conditions exist.

These exceptions are based on existing on-site conditions and cost-effectiveness.

Attic Insulation: Add attic insulation to a minimum level of R-38 in vented attics. This measure applies to homes according to vintage, building type and climate zone as defined in Table 6 and Table 7.

Exception 1: Buildings without vented attic spaces and buildings with existing attic insulation levels greater than R-19 in Climate Zones 1-5 and 8-16 and greater than R-5 in Climate Zones 6 and 7.

Air Sealing: Seal all accessible cracks, holes and gaps in the building envelope at walls, floors, and ceilings. Pay special attention to penetrations including plumbing, electrical, and mechanical vents, recessed can light fixtures, and windows. Weather-strip doors if not already present. Verification shall be conducted following a prescriptive checklist (to be developed) which outlines what building aspects need to be addressed by the permit applicant and verified by an inspector. Compliance can also be demonstrated with blower door testing showing at least a 30% reduction from pre-retrofit conditions. This measure applies to homes according to vintage, building type and climate zone as defined in Table 6 and Table 7.

Exception 1: Buildings that can demonstrate blower door test results showing 5 ACH50 or lower or can otherwise demonstrate that air sealing meeting the requirements of this ordinance was conducted within the last 12 months.

Duct Sealing: Air seal all ductwork to meet the requirements of the 2019 Title 24 Section 150.2(b)1E, with the exception that duct testing is not required to be verified by a HERS Rater. The duct system must be tested to confirm that the requirements have been met. The building department may allow the contractor to self-certify, may request to be present at the time of leakage testing, or may engage another third-party consultant to verify the duct sealing. See Appendix C – Standards Sections for additional details on the requirements per Title 24.

This measure applies to homes according to vintage, building type and climate zone as defined in Table 6 and Table 7.

Exception 1: All exceptions as stated in the 2019 Title 24 Section 150.2(b)1E are allowed.

Exception 2: Projects that require duct sealing as part of an HVAC alteration or replacement must meet all of the requirements of Title 24, Part 6, including HERS Rater verification.

Envelope & Duct Package: This is the combination of the Attic Insulation, Air Sealing, and Duct Sealing upgrades listed above.

Cool Roof: When replacing a roof, install a roofing product rated by the Cool Roof Rating Council to have an aged solar reflectance equal to or greater than 0.25, and a thermal emittance equal to or greater than 0.75, regardless of the compliance approach (prescriptive or performance). This measure only applies to steep slope roofs (ratio of rise to run greater than 2:12) and to buildings that are installing a new roof as part of the scope of Existing Building Efficiency Upgrade Cost-effectiveness Study 17 2019-12-19

the remodel and where more than 50 percent of the roof is being replaced. This applies only to certain homes according to vintage, building type and climate zone as defined in Table 6 and Table 7. Low slope roofs (ratio of rise to run of 2:12 or less) shall meet the requirements of Section 150.2(b)1Iii of 2019 Title 24 Standards. See Appendix C – Standards Sections for additional details on the requirements per Title 24.

Exception 1: Projects that are not installing a new roof as part of the scope. Only areas of roof that are to be re-roofed are subject to the cool roof upgrade.

Exception 2: All exceptions as stated in the 2019 Title 24 Section 150.2(b)1Ii for steep slope roofs and 150.2(b)1Iii for low slope roofs are allowed.

Windows: In a few climate zones, window upgrades were found to be cost-effective for the pre-1978 vintage buildings with existing single pane windows but is not included as a recommended measure. The cost requirement for window replacement is significant and the margin for cost-effectiveness is lower than many other measures.

Water Heating Package: Add exterior insulation meeting a minimum of R-6 to storage water heaters. Insulate all accessible hot water pipes with pipe insulation a minimum of ¾” inch thick. This includes insulating the supply pipe leaving the water heater, piping to faucets underneath sinks, and accessible pipes in attic spaces or crawlspaces. Upgrade fittings in sinks and showers to meet current CALGreen requirements.

Exception 1: Water heater blanket is not required on water heaters less than 20 gallons.

Exception 2: Water heater blanket not required if application of a water heater blanket voids the warranty on the water heater.

Exception 3: Fixtures with rated or measured flow rates no more than ten percent greater than current CALGreen requirements.

Exception 4: Water heater blanket is not required for multifamily buildings with central water heating systems.

Lighting – LED Lamps: Replace all interior and exterior screw-in (A-base) incandescent, halogen, and compact fluorescent lamps with screw-in LED lamps.

Existing Building Efficiency Upgrade Cost-effectiveness Study 18 2019-12-19

5.2 Other Considerations
HERS Field Verification: HERS field verification is not required to meet any of the requirements for the recommended measures unless the measure is used to meet Title 24 compliance. Measure installation shall be verified by a city building inspector or another third-party inspector deemed appropriate by the building department. While a HERS Rater is not required, one could be used as an alternative to inspections by the building department.

Combustion Appliance Safety and Indoor Air Quality: Implementation of some of the recommended measures will affect the pressure balance of the home which can subsequently impact the safe operation of existing combustion appliances as well as indoor air quality. Buildings with older gas appliances can present serious health and safety problems which may not be addressed in a remodel if the appliances are not being replaced. It is recommended that the building department require inspection and testing of all combustion appliances after completion of the retrofit work. It’s also recommended that jurisdictions require combustion safety testing by a certified professional whenever air sealing and insulation measures are applied, and existing combustion appliances are located within the pressure boundary of the building.

Jurisdictions may also want to consider requiring mechanical ventilation in homes where air sealing has been conducted. In older buildings, outdoor air is typically introduced through leaks in the building envelope. After air sealing a building, it may be necessary to forcefully bring in fresh outdoor air using supply and/or exhaust fans to minimize issues associated with indoor air quality.

Required Measures Included in Title 24 Performance Simulation: If any of the measures above are included in a performance Title 24 compliance report, it’s suggested that trade-offs be allowed as long as all minimum code requirements are met. For example, if a project is installing new windows and a new roof and insulating the attic and is demonstrating compliance with Title 24 with a performance simulation run, it would be acceptable if the installed roof did not meet the requirements listed above as long as this was traded off with either an increase in attic insulation or better performing windows. This would also allow trade-offs for projects that are installing high impact measures, such as solar water heating or whole house fans. This would require two simulation runs; however, it’s not expected this approach would be utilized often. Run #1 would evaluate the proposed building upgrades. This would also be the report submitted to the building department for the permit application demonstrating compliance with Title 24. Run #2 would also be completed with the minimum ordinance requirements modeled for each of the affected building components. In order to show compliance with the ordinance the applicant would need to demonstrate that the proposed upgrades (#1) would result in annual time dependent valuation (TDV) energy use equal to or less than the annual TDV energy use of the case based on the ordinance requirements (#2).

5.3 Next Steps
The focus of this study was to update the existing building upgrade cost-effectiveness study completed in June 2018 (Statewide Reach Codes Team, 2018), based on current utility rates and updated upgrade costs. Additional efforts have been identified that will be evaluated and released in an updated Existing Building Efficiency Upgrade Cost-Effectiveness Study in 2020. These include:
• Revisit base case assumptions for different vintages
• Additional HVAC upgrade options including:
o High efficiency equipment replacement as alternative to non-preempted upgrade o Air sealing and attic insulation at time of HVAC replacement o Improved duct insulation, tighter ducts, buried ducts • Additional building envelope improvements
Existing Building Efficiency Upgrade Cost-effectiveness Study 19 2019-12-19

o Higher ceiling insulation requirements
o Address low-slope roof replacements
• Lighting luminaire replacements in addition to lamp replacements • Evaluation of electrification measures at equipment change-out and electrification-ready • PV requirements at time of addition, and
• Additional efficiency upgrade requirements when installing PV

Existing Building Efficiency Upgrade Cost-effectiveness Study 20 2019-12-19

6 References
California Energy Commission. 2018a. 2019 Alternative Calculation Method Approval Manual. CEC-400-2018- 023-CMF. December 2018. California Energy Commission. https://www.energy.ca.gov/2018publications/CEC- 400-2018-023/CEC-400-2018-023-CMF.pdf
California Energy Commission. 2018b. 2019 Building Energy Efficiency Standards for Residential and Nonresidential Buildings. CEC-400-2018-020-CMF. December 2018. California Energy Commission. https://www.energy.ca.gov/2018publications/CEC-400-2018-020/CEC-400-2018-020-CMF.pdf ConSol. 2010. Water Use in the California Residential Home. January 2010. http://www.cbia.org/uploads/5/1/2/6/51268865/2010_-_chf_water_use_study.pdf

DEG. 2017. Large Scale Residential Retrofit Program. Prepared for the California Energy Commission by Davis Energy Group. January 2017.
http://www.energy.ca.gov/2017publications/CEC-500-2017-009/CEC-500-2017- 009.pdf
KEMA. 2010. Final Evaluation Report: Upstream Lighting Program, Vol 1. KEMA, Inc. February 2010. http://www.energydataweb.com/cpucfiles/18/finalupstreamlightingevaluationreport_2.pdf RSMeans. 2014. RSMeans Residential Cost Data 2014.

Statewide Reach Codes Team. 2018. Existing Building Efficiency Upgrade Cost-Effectiveness Study. June 8, 2018. https://localenergycodes.com/download/378/file_path/fieldList/Residential%20Retrofit%20Cost-Eff%20Report Existing Building Efficiency Upgrade Cost-effectiveness Study 21 2019-12-19

Appendix A – California Climate Zone Map

Existing Building Efficiency Upgrade Cost-effectiveness Study 22 2019-12-19

Appendix B – Utility Rate Tariffs
PG&E ............................................................................................................................................................ 23 SCE ............................................................................................................................................................... 25 SoCalGas ...................................................................................................................................................... 28 SDG&E .......................................................................................................................................................... 28 Escalation Assumptions ........................................................................................................................... 31

Existing Building Efficiency Upgrade Cost-effectiveness Study 23 2019-12-19

PG&E
The following pages provide details on the PG&E electricity and natural gas tariffs applied in this study. Table 8 describes the baseline territories that were assumed for each climate zone.

Table 8: PG&E Baseline Territory by Climate Zone
Baseline
Territory
CZ01 V
CZ02 X
CZ03 T
CZ04 X
CZ05 T
CZ11 R
CZ12 S
CZ13 R
CZ16 Y

The PG&E monthly gas rate in $/therm was applied on a monthly basis for the 12-month period ending January 2019 according to the rates shown below.

Existing Building Efficiency Upgrade Cost-effectiveness Study 24 2019-12-19

Existing Building Efficiency Upgrade Cost-effectiveness Study 25 2019-12-19

SCE

Existing Building Efficiency Upgrade Cost-effectiveness Study 26 2019-12-19

The following pages provide details on are the SCE electricity tariffs applied in this study. Table 9 describes the baseline territories that were assumed for each climate zone.

Table 9: SCE Baseline Territory by Climate Zone
Baseline
Territory
CZ06 6
CZ08 8
CZ09 9
CZ10 10
CZ14 14
CZ15 15

Existing Building Efficiency Upgrade Cost-effectiveness Study 27 2019-12-19

Existing Building Efficiency Upgrade Cost-effectiveness Study 28 2019-12-19

SoCalGas
Following are the SoCalGas natural gas tariffs applied in this study. Table 10 describes the baseline territories that were assumed for each climate zone.

Table 10: SoCalGas Baseline Territory by Climate Zone
Baseline
Territory
CZ05 2
CZ06 1
CZ08 1
CZ09 1
CZ10 1
CZ14 2
CZ15 1

Existing Building Efficiency Upgrade Cost-effectiveness Study 29 2019-12-19

SDG&E
Following are the SDG&E electricity and natural gas tariffs applied in this study. Table 11 describes the baseline territories that were assumed for each climate zone.

Table 11: SDG&E Baseline Territory by Climate Zone
Baseline
Territory
CZ07 Coastal
CZ10 Inland
CZ14 Mountain

Existing Building Efficiency Upgrade Cost-effectiveness Study 30 2019-12-19

Existing Building Efficiency Upgrade Cost-effectiveness Study 31 2019-12-19

Escalation Assumptions
The average annual escalation rates in the following table were used in this study and are from E3’s 2019 study Residential Building Electrification in California (Energy & Environmental Economics, 2019). These rates are applied to the 2019 rate schedules over a thirty-year period beginning in 2020. SDG&E was not covered in the E3 study. The Reach Code Team reviewed SDG&E’s GRC filing and applied the same approach that E3 applied for PG&E and SoCalGas to arrive at average escalation rates between 2020 and 2022.

Table 12: Real Utility Rate Escalation Rate Assumptions

Statewide Electric
Residential
Average Rate
(%/year, real)
Natural Gas Residential Core Rate
(%/yr escalation, real)
PG&E SoCalGas SDG&E
2020 2.0% 1.48% 6.37% 5.00%
2021 2.0% 5.69% 4.12% 3.14%
2022 2.0% 1.11% 4.12% 2.94%
2023 2.0% 4.0% 4.0% 4.0%
2024 2.0% 4.0% 4.0% 4.0%
2025 2.0% 4.0% 4.0% 4.0%
2026 1.0% 1.0% 1.0% 1.0%
2027 1.0% 1.0% 1.0% 1.0%
2028 1.0% 1.0% 1.0% 1.0%
2029 1.0% 1.0% 1.0% 1.0%
2030 1.0% 1.0% 1.0% 1.0%
2031 1.0% 1.0% 1.0% 1.0%
2032 1.0% 1.0% 1.0% 1.0%
2033 1.0% 1.0% 1.0% 1.0%
2034 1.0% 1.0% 1.0% 1.0%
2035 1.0% 1.0% 1.0% 1.0%
2036 1.0% 1.0% 1.0% 1.0%
2037 1.0% 1.0% 1.0% 1.0%
2038 1.0% 1.0% 1.0% 1.0%
2039 1.0% 1.0% 1.0% 1.0%
2040 1.0% 1.0% 1.0% 1.0%
2041 1.0% 1.0% 1.0% 1.0%
2042 1.0% 1.0% 1.0% 1.0%
2043 1.0% 1.0% 1.0% 1.0%
2044 1.0% 1.0% 1.0% 1.0%
2045 1.0% 1.0% 1.0% 1.0%
2046 1.0% 1.0% 1.0% 1.0%
2047 1.0% 1.0% 1.0% 1.0%
2048 1.0% 1.0% 1.0% 1.0%
2049 1.0% 1.0% 1.0% 1.0%
Existing Building Efficiency Upgrade Cost-effectiveness Study 32 2019-12-19

Appendix C – Standards Sections

6.1.1 2019 Building Energy Efficiency Standards Section 150.2(b)1I Roofs. Replacements of the exterior surface of existing roofs, including adding a new surface layer on top of the existing exterior surface, shall meet the requirements of Section 110.8 and the applicable requirements of Subsections i and ii where more than 50 percent of the roof is being replaced i. Low-rise residential buildings with steep-sloped roofs, in Climate Zones 10 through 15 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16 .

EXCEPTION TO 150.2(b)1Ii: The following shall be considered equivalent to Subsection i:
a. Air-space of 1.0 inch (25 mm) is provided between the top of the roof deck to the bottom of the roofing product; or
b. The installed roofing product has a profile ratio of rise to width of 1 to 5 for 50 percent or greater of the width of the roofing product; or
c. Existing ducts in the attic are insulated and sealed according to Section 150.1(c)9; or d. Buildings with at least R-38 ceiling insulation; or
e. Buildings with a radiant barrier in the attic meeting the requirements of Section 150.1(c)2; or f. Buildings that have no ducts in the attic; or
g. In Climate Zones 10-15, R-2or greater insulation above the roof deck. ii. Low-sloped roofs in Climate Zones 13 and 15 shall have a 3-year aged solar reflectance equal or greater than 0.63 and a thermal emittance equal or greater than 0.75, or a minimum SRI of 75.

EXCEPTION 1 to Section 150.2(b)1Iii: Buildings with no ducts in the attic.

EXCEPTION 2 to Section 150.2(b)1Iii: The aged solar reflectance can be met by using insulation at the roof deck specified in TABLE 150.2-B.

6.1.2 2019 Building Energy Efficiency Standards Section 150.2(b)1E Altered Space-Conditioning System - Duct Sealing: In all Climate Zones, when a space-conditioning system serving a single family or multifamily dwelling is altered by the installation or replacement of space -conditioning system equipment, including replacement of the air handler, outdoor condensing unit of a split system air conditioner or heat pump, or cooling or heating coil; the duct system that is connected to the altered space-conditioning system equipment shall be sealed, as confirmed through field verification and diagnostic testing in accordance with the applicable procedures for duct sealing of altered existing duct systems as specified in Reference Residential Appendix RA3.1 and the leakage compliance criteria specified in subsection i, ii, or iii below. Additionally, when altered ducts, air -handling units, cooling or heating coils, or plenums are located in garage spaces, the system shall comply with Section 150.2(b)1Diic regardless of the length of any new or replacement space-conditioning ducts installed in the garage space. i. The measured duct leakage shall be equal to or less than 15 percent of system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.1; or ii. The measured duct leakage to outside shall be equal to or less than 10 percent of system air handler airflow as determined utilizing the procedures in Reference Residential Appendix Section RA3.1.4.3.4; or iii. If it is not possible to meet the duct sealing requirements of either Section 150.2(b)1Ei or Section 150.2(b)1Eii, then, all accessible leaks shall be sealed and verified through a visual inspection and a smoke test by a certified HERS Rater utilizing the methods specified in Reference Residential Append ix RA3.1.4.3.5.

EXCEPTION 1 to Section 150.2(b)1E: Duct Sealing. Duct systems that are documented to have been previously sealed as confirmed through field verification and diagnostic testing in accordance with procedures in the Reference Residential Appendix RA3.1.

EXCEPTION 2 to Section 150.2(b)1E: Duct Sealing. Duct systems with less than 40 linear feet as determined by visual inspection.

Existing Building Efficiency Upgrade Cost-effectiveness Study 33 2019-12-19

EXCEPTION 3 to Section 150.2(b)1E: Duct Sealing. Existing duct systems constructed, insulated or sealed with asbestos.

6.1.3 2019 Building Energy Efficiency Standards Section 110.9(b)4 Occupant Sensing Controls. Occupant sensing controls include occupant sensors, motion sensors, and vacancy sensors, including those with a Partial-ON or Partial-OFF function. Occupant sensing controls shall:

A. Be capable of automatically turning the controlled lights in the area either off or down no more than 20 minutes after the area has been vacated;
B. For manual-on controls, have a grace period of no less than 15 seconds and no more than 30 seconds to turn on lighting automatically after the sensor has timed out; and C. Provide a visible status signal that indicates that the device is operating properly, or that it has failed or malfunctioned. The visible status signal may have an override that turns off the signal.

EXCEPTION to Section 110.9(b)4: Occupant Sensing Control systems may consist of a combination of single or multi-level Occupant, Motion, or Vacancy Sensor Controls, provided that components installed to comply with manual-on requirements shall not be capable of conversion by occupants from manual -on to automatic-on functionality

Existing Building Efficiency Upgrade Cost-effectiveness Study 34 2019-12-19

Appendix D – Measure Cost-effectiveness Tables
Climate Zone 1: The envelope and duct package is cost-effective for single family built before 1992 and multifamily homes built before 2006. For single family homes built between 1992 and 2005 duct sealing alone is cost-effective. Cool roof upgrades and window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 13: CZ 1 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 154 179 $3,472 $366 9.49 2.10
1978-1991 80 93 $3,212 $190 16.95 1.18
1992-2005 65 76 $3,212 $155 20.73 0.96
R-38 Attic Insulation
Pre-1978 50 57 $2,273 $119 19.17 1.04
1978-1991 23 27 $2,013 $55 36.46 0.55
1992-2005 23 26 $2,013 $54 37.14 0.54
Duct Sealing
Pre-1978 84 97 $240 $198 1.21 16.51
1978-1991 37 43 $240 $88 2.72 7.34
1992-2005 31 36 $240 $73 3.28 6.09
Cool Roof
Pre-1978 -28 -34 $635 -$68 -9.41 -2.12
1978-1991 -21 -25 $635 -$49 -12.88 -1.55
1992-2005 -22 -26 $635 -$52 -12.19 -1.64
Windows Pre-1978 111 130 $9,810 $265 37.08 0.54
Water Heating Package All Vintages 0 19 $208 $33 6.35 3.16 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.96 4.45 Table 14: CZ 1 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 58 67 $1,054 $137 7.72 3.15
1978-1991 28 33 $987 $56 17.59 1.38
1992-2005 21 25 $987 $41 24.21 1.00
R-38 Attic Insulation
Pre-1978 15 16 $594 $34 17.48 1.39
1978-1991 7 8 $526 $15 34.59 0.70
1992-2005 7 8 $526 $13 39.30 0.62
Duct Sealing
Pre-1978 32 37 $120 $76 1.57 15.47
1978-1991 12 13 $120 $24 4.99 4.88
1992-2005 8 10 $120 $16 7.55 3.22
Cool Roof
Pre-1978 -7 -9 $184 -$17 -10.60 -2.30
1978-1991 -4 -6 $184 -$10 -19.10 -1.27
1992-2005 -4 -6 $184 -$9 -20.78 -1.17
Windows Pre-1978 78 92 $5,873 $185 31.71 0.77
Water Heating Package All Vintages 0 16 $168 $28 6.02 4.07 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.96 4.45 Existing Building Efficiency Upgrade Cost-effectiveness Study 35 2019-12-19

Climate Zone 2: The envelope and duct package is cost-effective for single family homes built before 1978 and multifamily homes built before 2006. For single family homes built between 1978 and 2005 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for single family homes built before 1978 and multifamily homes built before 2006. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 15: CZ 2 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 578 109 $3,472 $387 8.97 2.17
1978-1991 194 51 $3,212 $154 20.80 0.94
1992-2005 125 45 $3,212 $117 27.47 0.72
R-38 Attic Insulation
Pre-1978 385 38 $2,273 $195 11.67 1.65
1978-1991 137 18 $2,013 $79 25.47 0.76
1992-2005 91 17 $2,013 $60 33.30 0.58
Duct Sealing
Pre-1978 203 56 $240 $169 1.42 13.77
1978-1991 52 21 $240 $55 4.39 4.50
1992-2005 31 20 $240 $44 5.50 3.60
Cool Roof
Pre-1978 219 -20 $635 $37 17.12 1.02
1978-1991 95 -15 $635 $8 76.43 0.19
1992-2005 47 -15 $635 -$9 -69.12 -0.33
Windows Pre-1978 529 39 $9,810 $246 39.93 0.48
Water Heating Package All Vintages 0 19 $208 $33 6.31 3.19 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.32 12.62 4.92 Table 16: CZ 2 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 224 40 $1,054 $136 7.76 3.05
1978-1991 89 18 $987 $52 18.83 1.25
1992-2005 69 15 $987 $42 23.26 1.02
R-38 Attic Insulation
Pre-1978 116 11 $594 $55 10.89 2.15
1978-1991 51 5 $526 $23 22.40 1.04
1992-2005 44 5 $526 $21 24.65 0.95
Duct Sealing
Pre-1978 112 22 $120 $72 1.67 14.16
1978-1991 44 6 $120 $23 5.22 4.50
1992-2005 26 5 $120 $16 7.49 3.15
Cool Roof
Pre-1978 94 -5 $184 $22 8.31 2.67
1978-1991 65 -3 $184 $17 10.98 2.04
1992-2005 45 -3 $184 $11 16.88 1.31
Windows Pre-1978 409 29 $5,873 $179 32.85 0.71
Water Heating Package All Vintages 0 16 $168 $27 6.16 3.98 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.32 12.62 4.92 Existing Building Efficiency Upgrade Cost-effectiveness Study 36 2019-12-19

Climate Zone 3: The envelope and duct package is cost-effective for single family and multifamily homes built before 1978. For single family and multifamily homes built between 1978 and 2005 duct sealing alone is cost- effective. Cool roof upgrades and window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 17: CZ 3 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 132 99 $3,472 $222 15.61 1.28
1978-1991 41 46 $3,212 $91 35.39 0.56
1992-2005 36 40 $3,212 $78 40.97 0.49
R-38 Attic Insulation
Pre-1978 74 37 $2,273 $91 24.87 0.80
1978-1991 17 17 $2,013 $36 56.57 0.35
1992-2005 16 17 $2,013 $33 60.55 0.33
Duct Sealing
Pre-1978 53 51 $240 $110 2.19 9.11
1978-1991 15 17 $240 $35 6.88 2.91
1992-2005 14 16 $240 $31 7.65 2.61
Cool Roof
Pre-1978 17 -18 $635 -$25 -25.51 -0.80
1978-1991 -9 -13 $635 -$24 -26.20 -0.76
1992-2005 -10 -13 $635 -$24 -26.17 -0.76
Windows Pre-1978 92 72 $9,810 $159 61.51 0.32
Water Heating Package All Vintages 0 19 $208 $33 6.39 3.15 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.75 4.52 Table 18: CZ 3 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 54 35 $1,054 $72 14.60 1.66
1978-1991 19 15 $987 $26 38.21 0.63
1992-2005 14 12 $987 $20 48.42 0.50
R-38 Attic Insulation
Pre-1978 26 10 $594 $25 24.16 0.99
1978-1991 10 5 $526 $10 53.48 0.45
1992-2005 8 5 $526 $9 57.71 0.42
Duct Sealing
Pre-1978 25 18 $120 $37 3.27 7.41
1978-1991 7 5 $120 $8 14.65 1.65
1992-2005 4 4 $120 $6 19.37 1.25
Cool Roof
Pre-1978 12 -4 $184 -$2 -78.18 -0.35
1978-1991 7 -3 $184 -$1 -167.26 -0.17
1992-2005 3 -3 $184 -$2 -76.88 -0.33
Windows Pre-1978 67 49 $5,873 $98 60.05 0.40
Water Heating Package All Vintages 0 16 $168 $26 6.41 3.82 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.75 4.52

Existing Building Efficiency Upgrade Cost-effectiveness Study 37 2019-12-19

Climate Zone 4: The envelope and duct package is cost-effective for single family homes built before 1978 and multifamily homes built before 1992. For single family homes built between 1978 and 2005 and multifamily homes built between 1992 and 2005 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for single family homes built before 1978 and multifamily homes built before 2006. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 19: CZ 4 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 560 93 $3,472 $349 9.95 1.95
1978-1991 228 44 $3,212 $146 21.94 0.89
1992-2005 158 38 $3,212 $116 27.80 0.70
R-38 Attic Insulation
Pre-1978 383 35 $2,273 $186 12.23 1.57
1978-1991 172 17 $2,013 $84 24.10 0.80
1992-2005 124 16 $2,013 $68 29.55 0.65
Duct Sealing
Pre-1978 185 46 $240 $144 1.67 11.73
1978-1991 60 17 $240 $48 5.04 3.88
1992-2005 34 15 $240 $37 6.53 3.02
Cool Roof
Pre-1978 240 -16 $635 $49 13.00 1.38
1978-1991 147 -12 $635 $29 21.69 0.82
1992-2005 87 -12 $635 $10 64.71 0.25
Windows Pre-1978 567 28 $9,810 $234 41.95 0.45
Water Heating Package All Vintages 0 19 $208 $33 6.33 3.18 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.32 12.63 4.92 Table 20: CZ 4 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 214 33 $1,054 $118 8.93 2.64
1978-1991 93 15 $987 $49 20.05 1.17
1992-2005 75 12 $987 $40 24.65 0.95
R-38 Attic Insulation
Pre-1978 114 10 $594 $51 11.61 2.01
1978-1991 53 5 $526 $23 22.89 1.02
1992-2005 47 5 $526 $21 24.91 0.94
Duct Sealing
Pre-1978 107 17 $120 $61 1.96 12.06
1978-1991 49 5 $120 $22 5.47 4.27
1992-2005 33 4 $120 $16 7.61 3.08
Cool Roof
Pre-1978 101 -4 $184 $26 7.19 3.12
1978-1991 75 -3 $184 $21 8.94 2.52
1992-2005 57 -3 $184 $15 12.49 1.80
Windows Pre-1978 438 21 $5,873 $173 34.01 0.68
Water Heating Package All Vintages 0 16 $168 $26 6.43 3.81 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.32 12.63 4.92 Existing Building Efficiency Upgrade Cost-effectiveness Study 38 2019-12-19

Climate Zone 5 PG&E/PG&E: The envelope and duct package is cost-effective for single family and multifamily homes built before 1978. For single family homes built between 1978 and 2005 and multifamily homes built between 1978 and 1991 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for multifamily homes built before 1978 but are not cost-effective for single family homes. Window replacements are cost- effective for multifamily homes built before 1978 but are not cost-effective for single family homes.

Note: Grey rows indicate option is not cost effective.

Table 21: CZ 5 PG&E/PG&E - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 105 102 $3,472 $215 16.12 1.24
1978-1991 42 48 $3,212 $92 34.85 0.57
1992-2005 36 41 $3,212 $79 40.63 0.49
R-38 Attic Insulation
Pre-1978 49 36 $2,273 $80 28.54 0.70
1978-1991 15 16 $2,013 $32 62.07 0.32
1992-2005 14 15 $2,013 $29 68.90 0.29
Duct Sealing
Pre-1978 46 52 $240 $107 2.24 8.93
1978-1991 16 18 $240 $36 6.70 2.98
1992-2005 15 17 $240 $33 7.17 2.79
Cool Roof
Pre-1978 -5 -25 $635 -$45 -14.14 -1.42
1978-1991 -14 -18 $635 -$36 -17.72 -1.13
1992-2005 -15 -19 $635 -$36 -17.70 -1.13
Windows Pre-1978 81 76 $9,810 $160 61.19 0.33
Water Heating Package All Vintages 0 19 $208 $33 6.40 3.14 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.88 4.48 Table 22: CZ 5 PG&E/PG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 45 36 $1,054 $260 4.06 5.76
1978-1991 13 15 $987 $19 53.03 0.46
1992-2005 10 13 $987 $15 64.74 0.38
R-38 Attic Insulation
Pre-1978 22 10 $594 $226 2.63 8.85
1978-1991 7 5 $526 $7 76.62 0.31
1992-2005 5 5 $526 $6 87.62 0.28
Duct Sealing
Pre-1978 20 19 $120 $234 0.51 45.53
1978-1991 5 4 $120 $5 21.88 1.11
1992-2005 3 4 $120 $5 26.51 0.92
Cool Roof
Pre-1978 7 -6 $184 $203 0.91 25.55
1978-1991 3 -3 $184 -$2 -75.95 -0.33
1992-2005 -1 -3 $184 -$4 -45.73 -0.53
Windows Pre-1978 59 52 $5,873 $280 20.98 1.12
Water Heating Package All Vintages 0 16 $168 $21 8.07 3.04 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.88 4.48 Existing Building Efficiency Upgrade Cost-effectiveness Study 39 2019-12-19

Climate Zone 5 – PG&E/SoCalGas: The envelope and duct package is cost-effective for multifamily homes built before 1978. For single family homes built before 2006 and multifamily homes built between 1978 and 1991 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for multifamily homes built before 1978 but are not cost-effective for single family homes. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 23: CZ 5 PG&E/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 105 102 $3,472 $165 20.98 1.00
1978-1991 42 48 $3,212 $69 46.38 0.45
1992-2005 36 41 $3,212 $60 53.86 0.39
R-38 Attic Insulation
Pre-1978 49 36 $2,273 $61 37.07 0.56
1978-1991 15 16 $2,013 $24 83.94 0.25
1992-2005 14 15 $2,013 $22 92.44 0.23
Duct Sealing
Pre-1978 46 52 $240 $82 2.92 7.20
1978-1991 16 18 $240 $27 9.04 2.32
1992-2005 15 17 $240 $25 9.51 2.21
Cool Roof
Pre-1978 -5 -25 $635 -$34 -18.44 -1.16
1978-1991 -14 -18 $635 -$28 -22.95 -0.92
1992-2005 -15 -19 $635 -$28 -22.62 -0.93
Windows Pre-1978 81 76 $9,810 $125 78.62 0.27
Water Heating Package All Vintages 0 19 $208 $26 7.95 2.69 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.88 4.48 Table 24: CZ 5 PG&E/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 45 36 $1,054 $216 4.89 4.80
1978-1991 13 15 $987 $19 53.03 0.48
1992-2005 10 13 $987 $15 64.74 0.40
R-38 Attic Insulation
Pre-1978 22 10 $594 $182 3.26 7.07
1978-1991 7 5 $526 $7 76.62 0.33
1992-2005 5 5 $526 $6 87.62 0.29
Duct Sealing
Pre-1978 20 19 $120 $191 0.63 36.87
1978-1991 5 4 $120 $5 21.88 1.16
1992-2005 3 4 $120 $5 26.51 0.97
Cool Roof
Pre-1978 7 -6 $184 $159 1.16 19.64
1978-1991 3 -3 $184 -$2 -75.95 -0.36
1992-2005 -1 -3 $184 -$4 -45.73 -0.56
Windows Pre-1978 59 52 $5,873 $236 24.87 0.95
Water Heating Package All Vintages 0 16 $168 $21 8.07 3.22 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.88 4.48

Existing Building Efficiency Upgrade Cost-effectiveness Study 40 2019-12-19

Climate Zone 6: The envelope and duct package is not cost-effective for single family or multifamily homes. For single family homes built before 1978 and multifamily homes built before 1992 duct sealing alone is cost- effective. Cool roof upgrades are cost-effective for multifamily homes built before 1992 but are not cost- effective for single family homes. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 25: CZ 6 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 455 54 $3,472 $211 19.98 0.78
1978-1991 144 22 $3,212 $69 56.35 0.28
1992-2005 95 19 $3,212 $47 81.42 0.19
R-38 Attic Insulation
Pre-1978 373 25 $2,273 $150 18.68 0.83
1978-1991 122 9 $2,013 $50 49.70 0.31
1992-2005 80 9 $2,013 $33 73.83 0.21
Duct Sealing
Pre-1978 114 23 $240 $65 4.38 3.54
1978-1991 33 6 $240 $18 16.35 0.95
1992-2005 19 6 $240 $12 23.93 0.65
Cool Roof
Pre-1978 195 -15 $635 $44 19.31 0.80
1978-1991 100 -9 $635 $25 34.16 0.45
1992-2005 53 -10 $635 $7 134.99 0.11
Windows Pre-1978 393 5 $9,810 $132 93.50 0.17
Water Heating Package All Vintages 0 19 $208 $26 9.05 1.72 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.25 15.73 3.95 Table 26: CZ 6 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 164 18 $1,054 $67 19.24 0.98
1978-1991 58 5 $987 $24 51.43 0.37
1992-2005 47 4 $987 $18 68.16 0.28
R-38 Attic Insulation
Pre-1978 107 7 $594 $39 18.98 1.00
1978-1991 41 2 $526 $14 45.11 0.42
1992-2005 35 2 $526 $12 53.10 0.36
Duct Sealing
Pre-1978 68 7 $120 $29 5.12 3.69
1978-1991 32 1 $120 $12 13.00 1.46
1992-2005 20 1 $120 $7 22.40 0.84
Cool Roof
Pre-1978 82 -3 $184 $21 11.31 1.67
1978-1991 60 -1 $184 $17 13.54 1.40
1992-2005 45 -1 $184 $12 20.06 0.94
Windows Pre-1978 321 6 $5,873 $101 73.32 0.26
Water Heating Package All Vintages 0 16 $168 $19 9.78 1.93 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.25 15.73 3.95

Existing Building Efficiency Upgrade Cost-effectiveness Study 41 2019-12-19

Climate Zone 7: The envelope and duct package is not cost-effective for single family or multifamily homes. For multifamily homes built before 1978 a combination of the duct sealing and R-38 attic insulation upgrades are cost effective. For single family homes built before 1978 and multifamily homes built between 1978 and 1991 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for single family homes built before 1978 and multifamily homes built before 1992. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 27: CZ 7 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 314 31 $3,472 $209 20.63 0.75
1978-1991 85 11 $3,212 $57 68.80 0.23
1992-2005 64 10 $3,212 $41 96.06 0.16
R-38 Attic Insulation
Pre-1978 272 16 $2,273 $168 16.91 0.92
1978-1991 76 6 $2,013 $46 54.75 0.28
1992-2005 59 6 $2,013 $33 75.36 0.21
Duct Sealing
Pre-1978 66 11 $240 $52 5.68 2.74
1978-1991 17 2 $240 $12 24.50 0.63
1992-2005 9 2 $240 $7 41.18 0.38
Cool Roof
Pre-1978 150 -11 $635 $66 12.43 1.25
1978-1991 65 -6 $635 $26 32.16 0.48
1992-2005 41 -7 $635 $9 100.28 0.15
Windows Pre-1978 293 -7 $9,810 $151 82.91 0.19
Water Heating Package All Vintages 0 19 $208 $30 7.92 1.96 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.33 12.01 5.17 Table 28: CZ 7 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 98 8 $1,054 $68 19.21 0.98
1978-1991 40 1 $987 $10 59.54 0.32
1992-2005 25 1 $987 $5 101.52 0.19
R-38 Attic Insulation
Pre-1978 66 3 $594 $47 15.72 1.20
1978-1991 30 1 $526 $0 44.99 0.42
1992-2005 20 1 $526 $0 71.64 0.26
Duct Sealing
Pre-1978 28 2 $120 $27 5.54 3.41
1978-1991 21 0.13 $120 $21 14.56 1.30
1992-2005 12 0.08 $120 $12 29.36 0.64
Cool Roof
Pre-1978 46 -3 $184 $29 8.01 2.36
1978-1991 47 -0.35 $184 $15 10.96 1.73
1992-2005 29 -0.35 $184 $9 20.10 0.94
Windows Pre-1978 235 -1 $5,873 $114 65.55 0.29
Water Heating Package All Vintages 0 16 $168 $24 7.98 2.37 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.33 12.01 5.17 Existing Building Efficiency Upgrade Cost-effectiveness Study 42 2019-12-19

Climate Zone 8: The envelope and duct package is cost-effective for single family built before 1978 and multifamily homes built before 1992. For single family homes built between 1978 and 2005 and multifamily homes built between 1992 and 2005 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 29: CZ 8 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 850 39 $3,472 $312 11.14 1.72
1978-1991 359 17 $3,212 $132 24.30 0.79
1992-2005 311 15 $3,212 $119 26.98 0.71
R-38 Attic Insulation
Pre-1978 590 18 $2,273 $201 11.28 1.69
1978-1991 266 8 $2,013 $92 21.90 0.87
1992-2005 248 8 $2,013 $90 22.33 0.85
Duct Sealing
Pre-1978 307 17 $240 $120 2.00 9.60
1978-1991 122 5 $240 $46 5.21 3.65
1992-2005 84 4 $240 $34 7.14 2.68
Cool Roof
Pre-1978 389 -10 $635 $108 5.89 3.13
1978-1991 266 -7 $635 $78 8.12 2.28
1992-2005 219 -8 $635 $66 9.67 1.90
Windows Pre-1978 723 4 $9,810 $222 44.12 0.43
Water Heating Package All Vintages 0 19 $208 $25 8.22 2.60 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.83 4.49 Table 30: CZ 8 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 312 13 $1,054 $103 10.21 2.28
1978-1991 139 4 $987 $46 21.31 1.08
1992-2005 123 3 $987 $42 23.65 0.98
R-38 Attic Insulation
Pre-1978 157 5 $594 $48 12.29 1.89
1978-1991 73 2 $526 $23 23.28 0.99
1992-2005 69 1 $526 $22 23.73 0.97
Duct Sealing
Pre-1978 171 5 $120 $57 2.10 11.02
1978-1991 83 1 $120 $27 4.45 5.15
1992-2005 64 1 $120 $22 5.56 4.12
Cool Roof
Pre-1978 149 -2 $184 $40 4.64 4.88
1978-1991 115 -1 $184 $33 5.56 4.10
1992-2005 99 -1 $184 $29 6.29 3.62
Windows Pre-1978 519 5 $5,873 $149 39.50 0.58
Water Heating Package All Vintages 0 16 $168 $20 8.54 3.04 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.83 4.49

Existing Building Efficiency Upgrade Cost-effectiveness Study 43 2019-12-19

Climate Zone 9: The envelope and duct package is cost-effective for single family built before 1992 and multifamily homes built before 2006. For single family homes built between 1992 and 2005 duct sealing alone is cost-effective. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 31: CZ 9 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,101 51 $3,472 $392 8.86 2.17
1978-1991 493 23 $3,212 $171 18.77 1.02
1992-2005 432 20 $3,212 $156 20.55 0.93
R-38 Attic Insulation
Pre-1978 649 22 $2,273 $215 10.55 1.81
1978-1991 305 11 $2,013 $98 20.45 0.93
1992-2005 299 10 $2,013 $102 19.74 0.96
Duct Sealing
Pre-1978 466 23 $240 $174 1.38 13.91
1978-1991 199 7 $240 $70 3.41 5.57
1992-2005 142 6 $240 $54 4.44 4.30
Cool Roof
Pre-1978 457 -12 $635 $122 5.22 3.53
1978-1991 319 -8 $635 $87 7.30 2.53
1992-2005 267 -9 $635 $75 8.44 2.19
Windows Pre-1978 941 9 $9,810 $285 34.43 0.55
Water Heating Package All Vintages 0 19 $208 $25 8.21 2.60 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.60 4.57 Table 32: CZ 9 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 418 17 $1,054 $135 7.84 2.97
1978-1991 201 6 $987 $65 15.12 1.53
1992-2005 168 5 $987 $54 18.23 1.27
R-38 Attic Insulation
Pre-1978 186 6 $594 $57 10.46 2.22
1978-1991 89 3 $526 $27 19.15 1.21
1992-2005 79 2 $526 $24 21.48 1.08
Duct Sealing
Pre-1978 245 8 $120 $78 1.53 15.13
1978-1991 122 1 $120 $38 3.17 7.24
1992-2005 95 1 $120 $30 4.04 5.68
Cool Roof
Pre-1978 179 -3 $184 $45 4.06 5.58
1978-1991 138 -2 $184 $37 4.96 4.58
1992-2005 111 -2 $184 $30 6.20 3.66
Windows Pre-1978 673 8 $5,873 $188 31.28 0.74
Water Heating Package All Vintages 0 16 $168 $19 8.81 2.95 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.29 13.60 4.57

Existing Building Efficiency Upgrade Cost-effectiveness Study 44 2019-12-19

Climate Zone 10 – SCE/SoCalGas: The envelope and duct package is cost-effective for single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are not cost-effective.

Note: Grey rows indicate option is not cost effective.

Table 33: CZ 10 SCE/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 1,354 57 $3,472 $470 7.39 2.59
1978-1991 597 25 $3,212 $206 15.62 1.22
1992-2005 516 22 $3,212 $180 17.81 1.07
R-38 Attic Insulation
Pre-1978 729 24 $2,273 $235 9.66 1.98
1978-1991 338 11 $2,013 $110 18.29 1.04
1992-2005 332 11 $2,013 $109 18.53 1.03
Duct Sealing
Pre-1978 617 25 $240 $221 1.09 17.63
1978-1991 248 8 $240 $89 2.69 7.06
1992-2005 186 7 $240 $69 3.50 5.44
Cool Roof
Pre-1978 555 -13 $635 $143 4.43 4.16
1978-1991 377 -9 $635 $105 6.05 3.06
1992-2005 315 -10 $635 $86 7.41 2.49
Windows Pre-1978 1,178 11 $9,810 $349 28.07 0.67
Water Heating Package All Vintages 0 19 $208 $25 8.24 2.59 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.30 13.28 4.68 Table 34: CZ 10 SCE/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 526 19 $1,054 $170 6.20 3.75
1978-1991 250 7 $987 $79 12.49 1.85
1992-2005 207 6 $987 $66 14.90 1.55
R-38 Attic Insulation
Pre-1978 221 7 $594 $70 8.52 2.72
1978-1991 106 3 $526 $32 16.44 1.41
1992-2005 91 3 $526 $29 18.31 1.26
Duct Sealing
Pre-1978 317 9 $120 $103 1.16 19.88
1978-1991 152 2 $120 $46 2.61 8.82
1992-2005 119 1 $120 $39 3.11 7.38
Cool Roof
Pre-1978 215 -3 $184 $57 3.22 7.03
1978-1991 163 -2 $184 $43 4.31 5.27
1992-2005 129 -2 $184 $35 5.21 4.36
Windows Pre-1978 840 10 $5,873 $235 24.97 0.92
Water Heating Package All Vintages 0 16 $168 $20 8.59 3.03 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.30 13.28 4.68

Existing Building Efficiency Upgrade Cost-effectiveness Study 45 2019-12-19

Climate Zone 10 – SDG&E: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for single family and multifamily homes built before 1978.

Note: Grey rows indicate option is not cost effective.

Table 35: CZ 10 SDG&E - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,354 57 $3,472 $800 4.34 4.37
1978-1991 597 25 $3,212 $359 8.95 2.12
1992-2005 516 22 $3,212 $317 10.13 1.87
R-38 Attic Insulation
Pre-1978 729 24 $2,273 $405 5.61 3.38
1978-1991 338 11 $2,013 $193 10.40 1.82
1992-2005 332 11 $2,013 $195 10.31 1.83
Duct Sealing
Pre-1978 617 25 $240 $377 0.64 29.78
1978-1991 248 8 $240 $155 1.55 12.20
1992-2005 186 7 $240 $120 2.00 9.47
Cool Roof
Pre-1978 555 -13 $635 $272 2.33 7.98
1978-1991 377 -9 $635 $195 3.26 5.71
1992-2005 315 -10 $635 $164 3.87 4.80
Windows Pre-1978 1,178 11 $9,810 $631 15.56 1.21
Water Heating Package All Vintages 0 19 $208 $30 6.87 3.01 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.50 8.02 7.75 Table 36: CZ 10 SDG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 526 19 $1,054 $298 3.54 6.52
1978-1991 250 7 $987 $141 6.98 3.30
1992-2005 207 6 $987 $116 8.54 2.70
R-38 Attic Insulation
Pre-1978 221 7 $594 $120 4.95 4.65
1978-1991 106 3 $526 $57 9.21 2.50
1992-2005 91 3 $526 $48 10.89 2.11
Duct Sealing
Pre-1978 317 9 $120 $180 0.67 34.43
1978-1991 152 2 $120 $84 1.43 16.04
1992-2005 119 1 $120 $67 1.79 12.77
Cool Roof
Pre-1978 215 -3 $184 $103 1.78 12.79
1978-1991 163 -2 $184 $80 2.30 9.91
1992-2005 129 -2 $184 $62 2.95 7.72
Windows Pre-1978 840 10 $5,873 $427 13.76 1.67
Water Heating Package All Vintages 0 16 $168 $25 6.79 3.71 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.50 8.02 7.75

Existing Building Efficiency Upgrade Cost-effectiveness Study 46 2019-12-19

Climate Zone 11: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for single family and multifamily homes built before 1978.

Note: Grey rows indicate option is not cost effective.

Table 37: CZ 11 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,827 120 $3,472 $774 4.48 4.27
1978-1991 858 55 $3,212 $358 8.96 2.13
1992-2005 770 48 $3,212 $324 9.93 1.92
R-38 Attic Insulation
Pre-1978 795 47 $2,273 $318 7.15 2.68
1978-1991 383 22 $2,013 $152 13.24 1.44
1992-2005 396 22 $2,013 $158 12.76 1.50
Duct Sealing
Pre-1978 982 61 $240 $415 0.58 33.10
1978-1991 434 20 $240 $174 1.38 13.77
1992-2005 355 18 $240 $147 1.64 11.65
Cool Roof
Pre-1978 624 -14 $635 $161 3.93 4.71
1978-1991 440 -10 $635 $118 5.40 3.44
1992-2005 369 -10 $635 $99 6.41 2.89
Windows Pre-1978 1,568 45 $9,810 $554 17.71 1.07
Water Heating Package All Vintages 0 19 $208 $34 6.06 3.32 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.35 11.53 5.39 Table 38: CZ 11 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 728 44 $1,054 $296 3.57 6.53
1978-1991 363 19 $987 $139 7.09 3.27
1992-2005 315 16 $987 $119 8.29 2.79
R-38 Attic Insulation
Pre-1978 268 13 $594 $102 5.80 4.00
1978-1991 131 6 $526 $49 10.75 2.15
1992-2005 118 6 $526 $43 12.10 1.91
Duct Sealing
Pre-1978 473 25 $120 $186 0.65 36.02
1978-1991 231 7 $120 $82 1.47 15.72
1992-2005 196 6 $120 $69 1.74 13.25
Cool Roof
Pre-1978 245 -4 $184 $66 2.76 8.21
1978-1991 189 -2 $184 $53 3.44 6.61
1992-2005 156 -2 $184 $45 4.13 5.51
Windows Pre-1978 1,107 33 $5,873 $387 15.19 1.52
Water Heating Package All Vintages 0 16 $168 $29 5.76 4.26 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.35 11.53 5.39

Existing Building Efficiency Upgrade Cost-effectiveness Study 47 2019-12-19

Climate Zone 12: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for multifamily homes built before 1978 but are not cost- effective for single family homes.

Note: Grey rows indicate option is not cost effective.

Table 39: CZ 12 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,209 109 $3,472 $579 6.00 3.21
1978-1991 540 51 $3,212 $263 12.23 1.57
1992-2005 471 45 $3,212 $229 14.02 1.37
R-38 Attic Insulation
Pre-1978 674 43 $2,273 $285 7.97 2.40
1978-1991 318 20 $2,013 $136 14.78 1.29
1992-2005 317 20 $2,013 $135 14.88 1.28
Duct Sealing
Pre-1978 532 55 $240 $272 0.88 21.82
1978-1991 216 20 $240 $107 2.24 8.57
1992-2005 155 18 $240 $83 2.89 6.67
Cool Roof
Pre-1978 479 -16 $635 $121 5.26 3.50
1978-1991 332 -12 $635 $87 7.33 2.51
1992-2005 273 -12 $635 $69 9.17 2.00
Windows Pre-1978 1,090 43 $9,810 $420 23.34 0.81
Water Heating Package All Vintages 0 19 $208 $34 6.05 3.32 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.34 11.80 5.26 Table 40: CZ 12 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 465 40 $1,054 $211 5.01 4.67
1978-1991 223 18 $987 $94 10.50 2.22
1992-2005 187 15 $987 $79 12.45 1.87
R-38 Attic Insulation
Pre-1978 199 11 $594 $80 7.40 3.14
1978-1991 97 6 $526 $37 14.03 1.65
1992-2005 88 6 $526 $35 15.14 1.53
Duct Sealing
Pre-1978 276 22 $120 $123 0.98 23.87
1978-1991 134 7 $120 $51 2.34 9.87
1992-2005 103 5 $120 $40 2.96 7.81
Cool Roof
Pre-1978 188 -4 $184 $51 3.63 6.23
1978-1991 146 -3 $184 $42 4.42 5.13
1992-2005 117 -3 $184 $33 5.49 4.13
Windows Pre-1978 785 31 $5,873 $294 19.96 1.16
Water Heating Package All Vintages 0 16 $168 $28 6.08 4.03 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.34 11.80 5.26

Existing Building Efficiency Upgrade Cost-effectiveness Study 48 2019-12-19

Climate Zone 13: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for single family and multifamily homes built before 1978.

Note: Grey rows indicate option is not cost effective.

Table 41: CZ 13 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 2,047 98 $3,472 $790 4.39 4.34
1978-1991 964 45 $3,212 $370 8.68 2.20
1992-2005 877 39 $3,212 $339 9.48 2.01
R-38 Attic Insulation
Pre-1978 940 37 $2,273 $338 6.72 2.83
1978-1991 451 18 $2,013 $162 12.43 1.53
1992-2005 463 17 $2,013 $168 11.97 1.59
Duct Sealing
Pre-1978 1,072 50 $240 $418 0.57 33.16
1978-1991 480 17 $240 $181 1.33 14.29
1992-2005 403 16 $240 $156 1.54 12.32
Cool Roof
Pre-1978 729 -15 $635 $186 3.41 5.45
1978-1991 516 -11 $635 $138 4.60 4.04
1992-2005 441 -11 $635 $117 5.41 3.43
Windows Pre-1978 1,604 41 $9,810 $547 17.94 1.06
Water Heating Package All Vintages 0 19 $208 $34 6.09 3.30 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.34 11.60 5.35 Table 42: CZ 13 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 805 36 $1,054 $298 3.54 6.55
1978-1991 407 16 $987 $144 6.85 3.37
1992-2005 353 13 $987 $126 7.85 2.94
R-38 Attic Insulation
Pre-1978 317 10 $594 $110 5.42 4.26
1978-1991 158 5 $526 $54 9.82 2.35
1992-2005 141 5 $526 $49 10.77 2.14
Duct Sealing
Pre-1978 510 20 $120 $185 0.65 35.73
1978-1991 254 6 $120 $85 1.42 16.22
1992-2005 214 5 $120 $73 1.64 13.98
Cool Roof
Pre-1978 283 -4 $184 $76 2.42 9.37
1978-1991 220 -3 $184 $62 2.99 7.62
1992-2005 183 -3 $184 $52 3.54 6.42
Windows Pre-1978 1,127 30 $5,873 $380 15.47 1.49
Water Heating Package All Vintages 0 16 $168 $27 6.13 4.00 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.34 11.60 5.35

Existing Building Efficiency Upgrade Cost-effectiveness Study 49 2019-12-19

Climate Zone 14 – SCE/SoCalGas: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for multifamily homes built before 1978 but are not cost-effective for single family homes.

Note: Grey rows indicate option is not cost effective.

Table 43: CZ 14 SCE/SoCalGas - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 1,832 121 $3,472 $680 5.10 3.80
1978-1991 844 55 $3,212 $316 10.18 1.90
1992-2005 746 48 $3,212 $285 11.28 1.71
R-38 Attic Insulation
Pre-1978 816 43 $2,273 $276 8.22 2.35
1978-1991 388 21 $2,013 $134 15.07 1.28
1992-2005 394 20 $2,013 $140 14.36 1.34
Duct Sealing
Pre-1978 967 63 $240 $366 0.66 29.52
1978-1991 417 21 $240 $154 1.56 12.34
1992-2005 333 19 $240 $130 1.84 10.44
Cool Roof
Pre-1978 631 -19 $635 $147 4.32 4.23
1978-1991 427 -14 $635 $108 5.88 3.12
1992-2005 359 -14 $635 $94 6.79 2.69
Windows Pre-1978 1,527 36 $9,810 $475 20.66 0.92
Water Heating Package All Vintages 0 19 $208 $26 8.02 2.66 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.31 13.03 4.77 Table 44: CZ 14 SCE/SoCalGas - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 731 45 $1,054 $259 4.07 5.78
1978-1991 364 19 $987 $125 7.90 2.96
1992-2005 310 16 $987 $107 9.23 2.53
R-38 Attic Insulation
Pre-1978 273 12 $594 $91 6.52 3.59
1978-1991 134 6 $526 $44 11.94 1.95
1992-2005 118 6 $526 $39 13.41 1.74
Duct Sealing
Pre-1978 467 25 $120 $162 0.74 31.67
1978-1991 227 7 $120 $73 1.64 14.14
1992-2005 188 6 $120 $62 1.93 11.99
Cool Roof
Pre-1978 250 -5 $184 $61 3.02 7.46
1978-1991 188 -3 $184 $50 3.71 6.11
1992-2005 152 -3 $184 $40 4.56 4.95
Windows Pre-1978 1,080 26 $5,873 $329 17.86 1.30
Water Heating Package All Vintages 0 16 $168 $22 7.76 3.35 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.31 13.03 4.77

Existing Building Efficiency Upgrade Cost-effectiveness Study 50 2019-12-19

Climate Zone 14 – SDG&E: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for single family and multifamily homes built before 1978.

Note: Grey rows indicate option is not cost effective.

Table 45: CZ 14 SDG&E - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,832 121 $3,472 $1,098 3.16 6.04
1978-1991 844 55 $3,212 $523 6.14 3.11
1992-2005 746 48 $3,212 $460 6.98 2.73
R-38 Attic Insulation
Pre-1978 816 43 $2,273 $452 5.03 3.79
1978-1991 388 21 $2,013 $223 9.04 2.11
1992-2005 394 20 $2,013 $228 8.85 2.15
Duct Sealing
Pre-1978 967 63 $240 $593 0.40 47.14
1978-1991 417 21 $240 $259 0.93 20.51
1992-2005 333 19 $240 $213 1.12 16.92
Cool Roof
Pre-1978 631 -19 $635 $285 2.23 8.31
1978-1991 427 -14 $635 $206 3.09 6.01
1992-2005 359 -14 $635 $170 3.72 4.97
Windows Pre-1978 1,527 36 $9,810 $815 12.04 1.57
Water Heating Package All Vintages 0 19 $208 $30 6.83 3.03 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.50 7.98 7.78 Table 46: CZ 14 SDG&E - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 731 45 $1,054 $431 2.45 9.49
1978-1991 364 19 $987 $209 4.72 4.90
1992-2005 310 16 $987 $174 5.66 4.09
R-38 Attic Insulation
Pre-1978 273 12 $594 $154 3.87 5.99
1978-1991 134 6 $526 $73 7.18 3.22
1992-2005 118 6 $526 $63 8.36 2.77
Duct Sealing
Pre-1978 467 25 $120 $272 0.44 52.62
1978-1991 227 7 $120 $125 0.96 23.98
1992-2005 188 6 $120 $103 1.16 19.86
Cool Roof
Pre-1978 250 -5 $184 $114 1.61 14.12
1978-1991 188 -3 $184 $87 2.12 10.73
1992-2005 152 -3 $184 $69 2.68 8.47
Windows Pre-1978 1,080 26 $5,873 $570 10.30 2.24
Water Heating Package All Vintages 0 16 $168 $26 6.54 3.85 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.50 7.98 7.78

Existing Building Efficiency Upgrade Cost-effectiveness Study 51 2019-12-19

Climate Zone 15: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for all single family and multifamily homes built before 2006. Window replacements are cost-effective for single family and multifamily homes built before 1978.

Note: Grey rows indicate option is not cost effective.

Table 47: CZ 15 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility Cost
Savings
Simple
Payback
Lifecycle
Benefit-Cost
Ratio
Envelope & Duct
Package
Pre-1978 4,141 23 $3,472 $1,116 3.11 6.04
1978-1991 2,041 8 $3,212 $559 5.75 3.27
1992-2005 1,877 7 $3,212 $526 6.10 3.08
R-38 Attic Insulation
Pre-1978 1,483 12 $2,273 $386 5.89 3.20
1978-1991 740 5 $2,013 $192 10.49 1.79
1992-2005 769 5 $2,013 $204 9.88 1.90
Duct Sealing
Pre-1978 2,494 9 $240 $680 0.35 53.24
1978-1991 1,182 2 $240 $331 0.73 25.86
1992-2005 1,039 1 $240 $299 0.80 23.41
Cool Roof
Pre-1978 1184 -5 $635 $296 2.15 8.72
1978-1991 854 -3 $635 $223 2.84 6.59
1992-2005 751 -3 $635 $201 3.15 5.93
Windows Pre-1978 3,214 4 $9,810 $840 11.68 1.61
Water Heating Package All Vintages 0 19 $208 $24 8.71 2.45 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.30 13.26 4.68 Table 48: CZ 15 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure Cost Utility Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 1,663 7 $1,054 $445 2.37 9.67
1978-1991 863 2 $987 $227 4.35 5.26
1992-2005 762 1 $987 $195 5.07 4.51
R-38 Attic Insulation
Pre-1978 574 3 $594 $156 3.82 6.00
1978-1991 285 1 $526 $77 6.87 3.33
1992-2005 254 1 $526 $64 8.20 2.79
Duct Sealing
Pre-1978 1,128 3 $120 $299 0.40 57.10
1978-1991 565 0.34 $120 $148 0.81 28.15
1992-2005 501 0.20 $120 $129 0.93 24.54
Cool Roof
Pre-1978 455 -1 $184 $113 1.63 14.00
1978-1991 351 -0.49 $184 $88 2.09 10.92
1992-2005 296 -0.45 $184 $72 2.54 9.00
Windows Pre-1978 2,237 4 $5,873 $581 10.11 2.26
Water Heating Package All Vintages 0 16 $168 $19 8.91 2.92 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.30 13.26 4.68

Existing Building Efficiency Upgrade Cost-effectiveness Study 52 2019-12-19

Climate Zone 16: The envelope and duct package is cost-effective for all single family and multifamily homes built before 2006. Cool roof upgrades are cost-effective for multifamily homes built before 2006 but are not cost-effective for single family homes. Window replacements are cost-effective for multifamily homes built before 1978 but are not cost-effective for single family homes.

Note: Grey rows indicate option is not cost effective.

Table 49: CZ 16 - Single Family Efficiency Upgrade Cost-effectiveness Results Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct Package
Pre-1978 635 231 $3,472 $620 5.60 3.52
1978-1991 286 119 $3,212 $307 10.46 1.89
1992-2005 240 107 $3,212 $271 11.87 1.66
R-38 Attic Insulation
Pre-1978 407 76 $2,273 $269 8.43 2.31
1978-1991 176 38 $2,013 $126 15.97 1.22
1992-2005 155 36 $2,013 $117 17.22 1.14
Duct Sealing
Pre-1978 236 128 $240 $307 0.78 25.32
1978-1991 103 60 $240 $141 1.70 11.65
1992-2005 79 55 $240 $125 1.92 10.34
Cool Roof
Pre-1978 232 -31 $635 $21 29.70 0.51
1978-1991 153 -23 $635 $11 56.27 0.24
1992-2005 107 -22 $635 -$3 -213.69 -0.18
Windows Pre-1978 267 162 $9,810 $376 26.11 0.76
Water Heating Package All Vintages 0 19 $208 $33 6.37 3.15 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.31 12.94 4.80 Table 50: CZ 16 - Multifamily Efficiency Upgrade Cost-effectiveness Results (Per Unit) Measure Vintage
Electricity
Savings
(kWh)
Gas
Savings
(therms)
Measure
Cost
Utility
Cost
Savings
Simple
Payback
Lifecycle
Benefit-
Cost Ratio
Envelope & Duct
Package
Pre-1978 243 88 $1,054 $236 4.48 5.36
1978-1991 119 45 $987 $104 9.45 2.53
1992-2005 98 38 $987 $84 11.80 2.03
R-38 Attic Insulation
Pre-1978 115 22 $594 $76 7.81 3.04
1978-1991 56 11 $526 $34 15.48 1.53
1992-2005 49 10 $526 $30 17.31 1.37
Duct Sealing
Pre-1978 131 54 $120 $138 0.87 27.75
1978-1991 63 22 $120 $55 2.20 10.87
1992-2005 47 20 $120 $43 2.80 8.56
Cool Roof
Pre-1978 100 -9 $184 $16 11.57 1.83
1978-1991 79 -6 $184 $15 11.88 1.83
1992-2005 60 -6 $184 $11 16.92 1.27
Windows Pre-1978 173 113 $5,873 $257 22.83 1.06
Water Heating Package All Vintages 0 16 $168 $28 6.01 4.08 LED Lamp vs. CFL All Vintages 1.2 0 $3.99 $0.31 12.94 4.80

Oakland City CouncilSeptember 15, 2025

Oakland City Council
September 15, 2025