Response to Public Comment Letter Received on May 21, 2026 Findings from Building Division’s review
Planning staff conducted a detailed review of the issues raised in the letter and consulted with the City’s Building Safety Division regarding the potential impacts of the proposed standards on building code compliance, energy efficiency, thermal performance, and structural design requirements. Based on this review, staff finds that the proposed Lower Density Residential Objective Design Standards would not adversely affect compliance with California Building Code requirements, including seismic standards, impede the installation of renewable energy systems, or preclude traditional residential design. Staff further find that the standards provide sufficient flexibility to accommodate a broad range of architectural styles, construction methods, and site design approaches.
The City’s Climate Action Playbook (CAP) identifies the Green Building Program as one of the City’s key implementation measures for reducing greenhouse gas emissions and advancing sustainability goals. The City’s award-winning Green Building Program promotes energy efficiency and high-performance building design. In addition to the Green Building Program, building code requirements support these objectives through provisions encouraging all-electric construction and requiring EV charging infrastructure and solar energy systems. The proposed objective design standards also include site design requirements that support sustainability goals, such as restrictions on invasive plant species and impermeable liners beneath artificial turf and permeable pavers.
Staff finds that the City’s sustainability and climate action objectives are achieved through the combined implementation of Green Building Program, building code requirements, and proposed objective design standards. Collectively, these requirements support energy- efficient and sustainable development while maintaining flexibility in site planning and building design.
Background on how the standards were developed and Public Engagement The proposed standards were developed through an extensive public process and informed by the City’s existing Single-Family Home Design Techniques, recurring concerns raised by community members through design review applications, staff experience administering residential development projects, consultant recommendations, Planning Commission feedback, and established architectural and urban design principles. The consultant team retained for the project included architects and urban design professionals who helped ensure that standards are practical, feasible, and responsive to a variety of architectural and site design conditions.
Project development began in June 2022 and included one community outreach meeting and three Planning Commission study sessions. Staff provided ongoing project notifications to interested parties and neighborhood associations and maintained a Attachment 10
dedicated project webpage containing draft documents, project updates, and meeting information. The interested parties also included architects and designers who regularly work with the City.
The first public draft was released in December 2025 and subsequently revised based on Planning Commission feedback and public comments, including updates to neighborhood definitions, removal of certain standards, revisions to prohibited material lists, and clarifications to architectural style examples and historic property provisions.
Design Standards Purpose
The primary purpose of the project is to replace the City’s existing subjective residential design guidelines with clear, objective, and measurable standards that provide greater predictability, consistency, and transparency for homeowners, applicants, staff, and decision-makers while ensuring compliance with state laws that limit the application of subjective design standards to housing development projects. A key goal of the standards is to maintain consistency with the established scale and minimize privacy concerns for Sunnyvale’s single-family neighborhoods while allowing flexibility, creativity, and a broad range of architectural and site design solutions.
How was the purpose achieved? How do these standards allow for more flexibility? To achieve this balance, the proposed standards are significantly more flexible than the City’s existing Single-Family Home Design Techniques. The standards provide alternative compliance options for many requirements and deviations of up to 25% from most numerical standards without requiring separate findings. Several standards also provide multiple compliance pathways, allowing applicants to select design solutions that best respond to site conditions, architectural style, sustainability goals, and construction considerations.
The proposed objective design standards are also accompanied by zoning code amendments intended to streamline the review process. These amendments include increasing design review thresholds at all review levels, increasing allowable lot coverage in single-family zoning districts, and updating green building provisions for consistency with current regulations.
How the design standards don’t require a wedding cake form Many of the standards are intended to address perceived building mass and scale rather than dictate specific architectural forms or construction methods. As a result, the standards can often be satisfied through a variety of design approaches and do not require a single design outcome. For example, the standards do not require a “wedding cake” building form. Instead, applicants may achieve compliance through a range of architectural techniques, including projections, recesses, roof articulation, material or color changes, Attachment 10
porches, bay windows, and other design elements that reduce visual massing while preserving design flexibility. The standards focus on achieving appropriate building scale rather than prescribing a particular architectural solution.
How the design standards don’t result in cookie cutter design In addition to site-planning and building-massing requirements, the proposed standards include Architectural Style Standards that apply to new dwellings and second-story additions. Appendix A supplements these standards by illustrating key design elements associated with architectural styles commonly found in Sunnyvale. The standards are intended to support architectural diversity and design flexibility by accommodating a broad range of styles.
Rather than prescribing a specific architectural style, the standards promote consistency and cohesiveness, enabling high-quality design while allowing creative solutions. They also recognize and accommodate the distinctive characteristics of different styles. Flexibility is built in to ensure that the standards reinforce and not conflict with the defining features of any given architectural style. For example, the use of a single exterior material is permitted when it is characteristic of the selected style. Overall, the standards do not require particular styles but instead offer a broader set of options for homeowners.
Conclusion
Overall, staff finds that the proposed standards strike an appropriate balance between preserving neighborhood scale and character, supporting housing development, advancing sustainability objectives, ensuring architectural consistency, and providing flexibility for a wide range of architectural, structural, and site design solutions. Staff further find that the proposed standards provide greater flexibility than the City’s existing guidelines while maintaining the core design objectives that residents, decision-makers, and stakeholders have consistently identified throughout the project.
A detailed itemized response to the specific comments and recommendations contained in May 21, 2026, letter is provided below.
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Detailed Response to the Letter
ITEM 2.2.1 AND 2.2.2.4
The letter states that the proposed limitation on second-floor area and restriction on uninterrupted two-story walls along the front façade constrain the ability of structural engineers to meet California’s seismic code requirements and increase construction cost and material use.
Staff Response
2.2.1.1 Second-to-First Floor Ratio
This standard is based on Guideline SF-1 of the City’s existing Single-Family Home Design Techniques, which limits the second-floor area to 35% of the first-floor area in predominantly one-story neighborhoods. The proposed objective design standards increase this allowance to 50% in predominantly one-story neighborhoods and up to 75% in all other neighborhoods.
For the purpose of calculating first floor area, the proposed standards include the primary dwelling unit, attached accessory dwelling units, attached garages and carports, entry porches and attached covered patios. Entry porches and attached covered patios are not included under the existing guidelines, thus resulting in a larger allowable second floor area.
In addition, staff is proposing to increase the maximum lot coverage in single-family zoning districts to 50%, compared to the current limits of 40% for two-story structures and 45% for one-story structures. This standard also provides flexibility by allowing a higher second to first floor ratio when three or more dwelling units within a neighborhood exceed the maximum ratio.
The purpose of this standard is to maintain compatibility with the established scale and character of existing single-family home neighborhoods. The increased ratios, expanded coverage, and alternative compliance provisions collectively provide greater flexibility for homeowners and developers while supporting compliance with the applicable building and seismic code requirements. The City’s Building Division has confirmed that the proposed standard would not impede compliance with California seismic code requirements.
2.2.2.4 Two-Story Wall Along the Front Elevation
This standard limits uninterrupted two-story wall segments without a vertical or horizontal break to no more than 25% of the front-elevation length. The requirement is based on existing Guidelines SF-5 and SF-7, which encourage a roof segment Attachment 10
between first- and second-floor walls and recommend limiting second-floor wall heights to reduce perceived second-floor bulk.
The proposed standard is more flexible than existing guidelines because it applies only to the front elevation. The required vertical or horizontal break may be achieved through a variety of architectural treatments including wall-plane changes, projections, recesses, roof elements, material or color changes, and decorative elements. These design techniques can satisfy the standard without necessarily requiring discontinuous structural wall planes while still achieving the intended objective of reducing the visual massing of two-story homes.
ITEM 2.2.3 ROOFS
The letter states that the roof-related design standards mandate roof complexity that could limit opportunities for on-site renewable-energy generation and increase construction costs.
Staff Response
2.2.3.1 Roof Materials
This standard requires textured or dimensional roofing materials. This requirement applies only to roofing material and does not regulate roof form, orientation, or design. As a result, it does not impact the installation of on-site renewable-energy systems.
2.2.3.2 Roof Spans
This standard requires homes with a front-elevation length greater than 45 feet to incorporate two or more roof spans along the front elevation. The requirement only applies to larger homes. A typical single-family lot in Sunnyvale is approximately 50 to 60 feet wide, after accounting for required setbacks, most homes do not exceed a 45 feet front elevation length. In addition, a roof over the entry porch counts as a separate roof span.
The purpose of the standard is to avoid large, uninterrupted roof spans on larger homes and maintain consistency with the scale and character of surrounding neighborhoods. The City’s Building Safety Division has confirmed that compliance with this standard would not limit the ability to install rooftop solar panels.
2.2.3.3 Roof Slope
This standard requires additions to match the existing roof pitch or be within a 1:12 difference. This provision does not regulate roof form or orientation and therefore does not affect solar installation opportunities.
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ITEM 2.2.4. FAÇADE ARTICULATION
The letter expresses concerns that wall-plane changes increase construction cost and reduces the thermal performance.
Staff Response:
This standard is based on existing Guideline SF-9, which recommends horizontal offsets along second-story walls at least every 24 feet. The proposed standard is more flexible, requiring a wall-plane change at least every 30 feet and only along the front elevation.
Wall-plane changes may be achieved through projections, recesses, entry porches, bay windows, or patios. Because entry porches are already required and are commonly incorporated into design, staff does not anticipate that compliance will be difficult.
The City’s Building Division has also confirmed that California Energy Code requirements focus on overall building airtightness and energy efficiency.
Air-tightness testing evaluates building openings such as doors, ducts, and windows rather than framing. Staff does not anticipate that compliance with this standard would adversely affect thermal performance.
ITEM 2.2.8.1 EXTERIOR WALL MATERIALS
The letter questions the requirement for multiple materials along the front elevation and its relationship to design quality.
Staff Response:
This standard requires at least two building materials or colors on the front elevation unless a single material or color is characteristic of the proposed architectural style.
The standard is consistent with existing Design Guidelines MA-1, MA-2, and MA-3, which encourage a mix of materials, consistency with architectural style, and appropriate carry-over of materials onto the sides of homes. The use of complementary materials and colors is a widely accepted design practice that helps provide visual interest, articulation, and compatibility with neighborhood character while allowing flexibility for a variety of architectural styles.
PICTURES USED UNDER “STYLE” EXAMPLES
The letter states that none of the pictures used in Appendix A were taken in Sunnyvale.
Staff Response:
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Staff notes that this statement is not accurate. With the exception of the top image for the Craftsman style (page 41) and the Prairie style (page 43), all of the pictures included in Appendix A were taken within Sunnyvale.
These images were intentionally selected to illustrate architectural styles commonly found throughout Sunnyvale neighborhoods and to provide local examples that residents and applicants may readily recognize.
1234 CRANBERRY AVENUE EXAMPLE
The letter states that Sunnyvale’s oldest home would not comply with the proposed design standards.
Staff Response:
The residence at 1234 Cranberry Avenue was originally constructed in 1862 as a part of a 320-acre ranch and represents a unique historic resource that significantly differs from conventional single-family homes found throughout Sunnyvale. The property is situated on an unusually large lot (over 21,000 s.f.) and is oriented at an angle to the street, a condition that is not representative of typical residential neighborhoods.
If the design standards are applied objectively, staff believe that the home would comply with most proposed design standards. The one-story portion of the structure faces the street, the front façade is less than 45 feet wide, and use of single exterior material is consistent with the building’s Colonial architectural style.
RESPONSE TO RECOMMENDATIONS
Climate Action Playbook (CAP)
The letter recommends considering options that support City’s Climate Action Plan (CAP).
Staff Response:
The City’s Green Building Program is one of the implementation measures identified in C A P. The green building program and applicable building code support sustainability goals through provisions encouraging all electric construction, requiring EV charging infrastructure and solar panel requirements. The proposed design standards also advances these goals by including provisions related to site design, including restrictions on invasive plants and impermeable lining beneath artificial turf and permeable pavers.
Second Floor Limit
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The letter suggests removing or relaxing the proposed design standards to allow larger second floor area and not require wall plane articulation and instead retaining the city’s existing solar access requirements.
Staff Response:
The proposed second-to-first-floor ratio is derived from our existing guidelines. Staff is proposing several changes that offer greater flexibility and support larger homes and expanded second-floor areas. Staff is proposing increased second-floor ratios, increased lot coverage allowance, inclusion of patios and entry porches in first floor area and alternative compliance options that provide increased flexibility and support larger homes and second floor areas.
In addition, staff is proposing to increase design review thresholds for Planning Commission review from 45 percent Floor Area Ratios (FAR) to 60 percent FAR, that will further streamline the review process.
Parking Requirements
The letter recommends reducing the parking requirement for single-family homes.
Staff Response:
Parking requirements are outside the scope of this project and will be evaluated through the City’s ongoing residential parking study.
Solar Orientation
The letter recommends encouraging home designs that prioritize solar orientation rather than orienting buildings toward the street.
Staff Response:
Building setbacks and other development standards are not part of the project scope. In addition, conventional lot sizes and regular lot configurations limit the ability to orient homes primarily for solar access. Designers and architects have greater flexibility to achieve optimal solar orientation on larger or uniquely shaped lots.
Demonstrate applicability for existing homes
The letter recommends demonstrating how existing homes can comply with any proposed standards.
Staff Response:
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The proposed standards were developed through an extensive public process and informed by the City’s existing Single-Family Home Design Techniques, recurring concerns raised by community members during design review applications, staff experience administering residential development projects, consultant recommendations, Planning Commission feedback, and established architectural and urban design principles. The consultant team included architects and urban design professionals who helped ensure the standards are practical, feasible, and responsive to a variety of architectural styles and site conditions.
The purpose of the design standards is to guide future development and remodels; they are not intended to retroactively require existing homes to comply. Many existing Sunnyvale homes were constructed under different zoning standards and building codes, and it is common for updated design standards to reflect evolving community priorities, construction practices, and state law requirements.
Staff reviewed the proposed standards to ensure they are achievable for typical single-family lots and do not create infeasible development scenarios. Property owners will continue to have flexibility in how they remodel or expand their homes, including through alternative compliance and exception options. Existing homes will not be required to conform unless a future project triggers design review under the proposed standards.
Staff will continue to monitor the implementation of the standards and, if needed, will return with recommended adjustments in two years.
Structural engineers review
The letter recommends requiring that the design be reviewed by reputable structural engineers and energy modelers to confirm compliance with Building Code requirements and CAP goals.
Staff Response:
The proposed design standards were reviewed by City’s Building Division staff, who confirmed that the design standards would not impede compliance with applicable seismic code requirements or CAP’s goals. The Building Safety Division includes several licensed structural engineers and a licensed architect. Staff also coordinated with City Attorney’s Office and Environmental Services Department (ESD) to ensure consistency with state law requirements and the City’s sustainability objectives.
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