Redwood City — the San Mateo County seat — carries the county’s most varied housing stock. The revitalized downtown around Broadway and the Caltrain station sits amid older bungalow and craftsman neighborhoods; the El Camino Real corridor runs the length of the city with mid-century apartments and commercial; and Redwood Shores, out by the bay, is a planned community of newer homes near the Oracle campus. That range means nearly every ADU type has a natural home somewhere in the city.
In the older bungalow neighborhoods near downtown, the most common paths are garage conversions and attached additions — deep lots, established footprints, and homes with the character to extend gracefully. Converting an existing garage keeps construction efficient and, under state law, generally cannot be burdened with replacement parking requirements. Where lots run deeper, a detached ADU up to 1,200 square feet is often feasible: a true backyard cottage with private outdoor space that works for rental income or multigenerational living.
Junior ADUs (JADUs) are a strong fit across Redwood City’s older housing stock. Carving a compact, up-to-500-square-foot unit out of existing living space gives homeowners a low-cost entry point — a space for an aging parent, a home office with a kitchenette, or a modest rental — with no new foundation and no exterior change. State law prohibits cities from requiring owner-occupancy for standard ADUs, so most Redwood City ADU projects can be rented to long-term tenants without the homeowner living on site.
Redwood City ADU permits route through the city’s Community Development Department, and California’s ministerial (by-right) approval process applies — a compliant project cannot be subjected to discretionary hearings. State law caps required side and rear setbacks at 4 feet. The practical wrinkles vary by neighborhood: downtown-adjacent bungalows often need electrical panel and sewer lateral evaluations given the age of the stock, while hillside parcels on the city’s western edge can need a grading review. We confirm all of it during feasibility so the design is submitted once and submitted right.
Rental demand in Redwood City is deep: the county government employment base, the downtown Caltrain station, the Oracle and Redwood Shores campuses, and the broader 101 corridor all feed a strong tenant pool. The city’s “Climate Best by Government Test” motto aside, the real draw for ADU owners is simple — steady commuter demand and a downtown that keeps getting more walkable. Whether the goal is monthly income, housing for family, or both, the project works when the unit is designed right and permitted correctly the first time.
Ready to find out what your Redwood City lot can carry? ADU Cities is a Southern California ADU design-build firm — we handle feasibility, design, permits, and construction under one roof. Call 562.810.1965 for a free consultation and site evaluation. CSLB #1138550.
