Sunnyvale is getting ready to trade lab coats for front porches.
The Sunnyvale Planning Commission on Monday signed off on a plan to tear down two aging office and research campuses on De Guigne Drive and replace them with 370 homes, voting 6-0 to move the proposal forward. The project would bring 329 primary for-sale units plus 41 accessory dwelling units, reshaping the eastern edge of Sunnyvale and, according to planners and neighbors, cranking up pressure on local services and traffic mitigation.
The proposal calls for demolishing the office buildings at 510 and 920 De Guigne Drive and building a mix of townhomes and smaller multi-family buildings in their place, according to The Mercury News. The application, led by an affiliate of Tidewater Capital, lays out the 329 for-sale units and 41 accessory units and includes new streetscape features and open space meant to stitch the project into the surrounding neighborhood rather than wall it off.
An affiliate of Tidewater Capital spent about $65 million in 2024 to buy portions of the site, a deal that industry watchers said set up the conversion of underused office parks into housing. The Real Deal reported that purchase and pointed to broader office vacancies across Silicon Valley that have made housing-focused redevelopments far more attractive to investors.
Neighbors warn of traffic and thin services
Residents near the site are bracing for a lot more cars and not nearly enough neighborhood amenities to support them.
"Adding the vehicle load of over 360 new households will drastically increase traffic density," Sunnyvale resident Lei Duan wrote to the city, arguing that local streets are already feeling crowded. Neighborhood advocate Christina O'Guinn added that north Sunnyvale "has long faced underinvestment and still lacks full-service grocery stores," according to The Mercury News. Taken together, the comments paint a picture of a part of town that wants housing but is nervous about what happens when 370 new households all try to run errands at the same time.
Design, waivers and environmental homework
Planning commissioners are not done kicking the tires on the design details.
At an earlier study session, commissioners pressed the developer for clearer visuals and a stronger, unit-by-unit case for several requested waivers, including reduced setbacks and specific material choices. A summary of that meeting notes that city staff will require a formal environmental checklist along with more detailed plans for open space, tree replacement and soil remediation before the project can secure final entitlements, according to Citizen Portal.
In other words, the basic concept is in play, but the fine print on how green, how safe and how comfortable the site will be is still very much under review.
What comes next at City Hall
The commission's unanimous vote sends the project into Sunnyvale's remaining review gauntlet, which still includes additional public hearings, environmental review and eventual consideration by the City Council. The city's planning pages outline how public hearings work and how notices are posted, and staff say the developer is expected to come back with supplemental exhibits and detailed, unit-level justifications for its requests at the next formal hearing, according to Sunnyvale.
The offices at 510 and 920 De Guigne Drive may be living on borrowed time, but the debates over how exactly to turn them into homes are only just getting started.
