Alameda, CA Building Setbacks & Zoning: Lot Coverage Limits (2026)

The City of Alameda limits the share of a lot a main building may cover, set by zoning district in AMC Section 30-4. The R-1 single-family district (30-4.1) limits maximum main building coverage to 48% of lot area, with a minimum lot area of 5,000 square feet and a minimum lot width of 50 feet. The R-2 (30-4.2), R-3 (30-4.3), R-4 (30-4.4), and R-5 (30-4.5) districts allow maximum main building coverage of 53% of lot area, and the higher-density R-6 district (30-4.6) allows up to 60%. "Main building coverage" refers to the footprint of the principal structure as a percentage of the lot. These coverage caps operate alongside the required yards (20-ft front, 5-ft side, 20-ft rear) and the district height limits to manage overall bulk and preserve the open, garden-city character of Alameda's neighborhoods. State housing laws modify these standards in some cases: under SB 9 / Government Code 66411.7 urban lot splits, each resulting lot must be at least 1,200 square feet and at least 40% of the original lot, and objective standards such as minimum lot width and maximum building coverage cannot be applied where they would physically preclude a qualifying two-unit development or lot split. Accessory dwelling units are also governed by state-mandated standards. Because coverage limits vary by district, verify the parcel's exact zoning before designing.