Average Units per Acre of Newly Approved Residential Development
City Planning and Housing Departments of Silicon Valley
Silicon Valley Institute for Regional Studies
Data are from Joint Venture Silicon Valley’s annual land-use survey of all cities within Silicon Valley. The 33 cities/counties included in the FY 2019-20 Residential Density analysis are Atherton, Belmont, Brisbane, Burlingame, Campbell, Colma, County of San Mateo, County of Santa Clara, Daly City, East Palo Alto, Foster City, Fremont, Gilroy, Half Moon Bay, Hillsborough, Los Altos Hills, Los Gatos, Millbrae, Morgan Hill, Mountain View, Newark, Pacifica, Palo Alto, Redwood City, San Bruno, San Carlos, San Mateo, San Jose, Santa Clara, Saratoga, South San Francisco, Sunnyvale, and Woodside. Most recent data are for fiscal year 2019 (July 2018-June 2019). Residential density was calculated as the average residential density of the participating cities. Beginning in 2014, the residential density analysis began to exclude secondary units that were approved with the primary unit. Beginning in 2020, the residential density calculation included accessory dwelling units (ADUs) that were issued a building permit in lieu of a planning approval.
Beginning in 2008, the Land Use Survey expanded its geographic definition of Silicon Valley to include cities northward along the U.S. 101 corridor (Brisbane, Burlingame, Millbrae, San Bruno and South San Francisco). In 2014, the Survey expanded to include all Silicon Valley cities (adding Colma, Daly City, Half Moon Bay and Pacifica). Beginning in 2020, the residential density calculation included accessory dwelling units (ADUs) that were issued a building permit in lieu of a planning approval.