Alameda, CA Accessory Structures: Shed & Carport Rules (2026)

Alameda's accessory-building standards sit in Section 30-5.7.f, the same section that governs yard encroachments generally. A shed, detached garage or other accessory building is limited to one story and ten feet in height at the top of a parapet or where the side wall meets the roof, though the code allows the roof ridge to reach fifteen feet under a specific exception. Coverage is capped separately: an accessory building cannot cover more than six hundred square feet or sixty percent of the zoning district's minimum required rear yard, whichever number is larger, and any portion built outside that minimum rear yard still counts against the lot's overall maximum building coverage.

Setbacks depend on how far back the structure sits. Within seventy-five feet of the front property line, an accessory building must keep a five-foot side yard setback. Beyond seventy-five feet from the front property line, the code allows the building to be built up to the interior side property line itself, so long as any construction within three feet of that line meets a one-hour fire-resistive standard approved by the Building Official. A similar rear-yard rule lets a shed be built to the rear property line when it backs up to a neighbor's own required rear yard, again subject to the three-foot fire-resistive construction requirement.

These are zoning dimensional standards; a shed over a certain size or with electrical or plumbing work still needs its own building permit under Alameda's building code, separate from the zoning compliance addressed here.