Passive House BB
2875 21st Street, #4
San Francisco, CA 94110
CA Architecture License #: C36261
415.819.7978
Mar
ch 11, 2026
At
tn: Mayor Larry Klein, Sunnyvale City Councilors
cc. Ms. Aastha Vashist, Senior Planner
City of Sunn
yvale
456 West Olive Avenue
Sunnyvale
CA 94086
Re: Lower Density Residential Objective Design Standards DRAFT
A CALL FOR SUNNYVALE TO FOLLOW THE PATH OF THE SUN
Dear
Mayor Klein and esteemed Members of the Sunnyvale City Council, As an ar
chitect specializing in high performance custom homes, with notable experience in delivering projects in the City of Sunnyvale1, I’m writing to express my dismay at the direction proposed by the Sunnyvale Planning Department in the draft update to its ‘Lower Density Residential Objective Design Standards.’
While
I fully recognize this update is driven by recent State law, requiring cities to remove all subjective design requirements from their zoning and design guidelines, I’d like to illustrate why imposing a matrix of arithmetic calculations on lower density zones is not the way to go. Rather than simply critiquing the existing proposal, I’ve added suggestions for how the City Council may better guide the Planning Department to achieve more productive outcomes.
Firs
t I’d like to identify a few problematic requirements in the draft proposal here:
1 Sunnyvale I : Studied by DOE Build America program: ‘Sunnyvale Marine Climate Deep Energy Retrofit.’
https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/sunnyvale-marine-cli mate-retrofit.pdf
Sunnyvale II: Awarded the first All-Electric Residential Home design award by Peninsula Clean Energy and included as one of two Californian Passive House projects in a study by the California Public Utility Commission report on ‘Grid Benefits of Passive Houses’:
https://www.cpuc.ca.gov/-/media/cpuc-website/divisions/energy-division/documents/building-de carb/passive-house-phase-i-report.pdf
Attachment 9
1. Items 2.2.1 and 2.2.2.4: limit to second floor area, compounded with limits to continuous vertical planes of first and second floors. This severely constrains the ability of structural engineers to meet California’s seismic code. Shear walls need continuous planes and discontinuous vertical planes create complex engineering and add unnecessary cost and materials.
2. Items 2.2.3: forced complexity of roof shapes. Complex roof designs significantly limit on-site renewable energy generation while increasing onsite renewable energy installation costs. Energy is already expensive. Why make it more so?
3. Items 2.2.4: mandating horizontal wall plane changes adds cost and complexity and reduces the thermal resilience of these walls. For every corner you add, more framing, less insulation and more opportunities for leaks occur. The need for this level of articulation is at base a subjective opinion on what constitutes ‘good design.’ Please don’t fall for this canard.
4. Item 2.2.8.1: Layering on requirements for additional materials adds insult to injury.
How does mandating multiple siding materials ensure good design?
Fig. 1-4: Images excerpted directly from Lower Density Residential Objective Design Standards DRAFT prepared by Dahlin for City of Sunnyvale Planning Department.
When you mandate complex forms with misaligned vertical and horizontal loads you increase all material requirements, including steel and concrete. By doing so, you also eliminate the opportunity to build homes using modern means of construction, so you almost guarantee material waste. Furthermore, all additional materials needlessly increase the embodied carbon emissions generated from transportation.
2 Attachment 9
It should be noted that none of the homes used as ‘style’ examples in this proposal appear to be in Sunnyvale. It would be a challenge for any firm to replicate any of the existing home patterns found across Sunnyvale and have them meet these proposed requirements. More ironically, it must be politely pointed out that the oldest house in Sunnyvale would not comply with these guidelines since it uses only one siding material, exceeds the 25% continuous wall plane limit on the front facade and the second story is visibly more than 50% of the lower floor area.
If the oldest home in Sunnyvale cannot comply with these proposed guidelines, are they a good fit for Sunnyvale?
Fig. 2: Image of William Wright Ranch house - the oldest house in Sunnyvale. Source:
https://www.hmdb.org/m.asp?m=154935
I sincerely believe that Sunnyvale’s City Planners would encourage good design choices, if they were actively directed by the City Council to find options that also support Sunnyvale’s Climate Action Playbook, which includes two clear goals: 1. promoting clean electricity; and 2. decarbonizing buildings. As someone with established credentials designing buildings that deliver both outcomes, I respectfully offer the following suggestions for how Sunnyvale may encourage better home designs in its low-rise residential areas:
Allow two-story homes by right, with no ‘x% of lower floor’ limits, limits to vertical alignment or limits based on existing number of two-story homes. However, retain the current limit to the amount of shade allowed to be cast onto neighbor’s roofs. This 3 Attachment 9
automatically keeps upper floor sizes respectful of neighboring homes without requiring arithmetical gymnastics, plus optimizes roof space for renewable energy generation.
Alternately, offer higher percentage second floor area, plus increased vertically aligned wall allowances for designs that reduce their lower floor footprints. Building second story homes should not become a percentage calculation crime in Sunnyvale. Adding a second floor to an existing home is the most cost-effective, lowest embodied carbon way to add gentle density to your city, without paving over every inch of greenspace in Sunnyvale.
Encourage homes to consider good solar orientation, rather than require all designs to address the street directly. This allows designers to integrate passive solar design to naturally reduce heating and cooling loads via correct solar orientation and with shading that is optimized for the sun’s path.
Limit required parking to one parking space only and include a requirement to install EV charging. Current R-0 zoning requires two covered and two additional off-street parking spaces. This adds up to a minimum of 740 sf, which on an average 7,000 sf lot equals
10.5 % of the total lot area. This is hypocritical for a Silicon Valley city filled with residents actively promoting self-driving transport - and ridiculously excessive for a neighborhood filled with only 3 bedrooms.
Require that the Planning Department demonstrate how existing Sunnyvale homes can comply with any new design guidelines they propose.
Require all these designs to be reviewed by a team of reputable structural engineers and energy modelers to confirm that all new design guidelines actually do deliver homes that will be safe to live in and will not actively undermine the stated goals of Sunnyvale’s approved Climate Action Plan.
I look
forward to designing many more projects in the City of Sunnyvale, and supporting its leadership in providing an exemplary place to live and work in the greater Bay Area. To that end, I strongly encourage Sunnyvale’s City Council to direct the Planning Department to revisit their draft guideline and come back to you - and the residents of Sunnyvale - with a revised plan that will deliver well designed housing that is safe to live in, affordable to build and supports Sunnyvale’s exemplary Climate Action Playbook.
Since
rely yours,
Br
onwyn Barry, RA, CPHD
Principal - Passive House BB
Cc. Jeremy Madsen, Executive Director: Build It Green
Corey Smith, Executive Director: Housing Action Coalition Sonja Trauss, Executive Director: Yimby Law
4 Attachment 9