Skip to content

Alameda County · Building on your lot

Sheds, garages and other accessory structures in Alameda County

In R districts, the county limits detached accessory buildings to one story and 15 feet, at least 6 feet from other buildings.

Ask about sheds, garages and other accessory structures in Alameda County See coverage

Key points

  • Accessory buildings: In R districts, the county limits detached accessory buildings to one story and 15 feet, at least 6 feet from other buildings.

Each rule below links to the section of the Alameda County Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Alameda County's code says

Alameda County code What Alameda County's code adds
Maximum height
  • No more than 1 story and no taller than 15 feet.
    Applies: Detached accessory buildings in an R district.
    § 17.52.260 · code text
    No detached accessory building in an R district shall be located within six feet of any other building on the same lot, or have more than one story or a height in excess of fifteen (15) feet.
Side and rear setback
  • At least 6 feet from the side line of the front half of a neighboring lot.
    Applies: Accessory buildings in an R district.
    § 17.52.270 · code text
    No accessory building in any R district shall be within six feet of the side line of the front half of any abutting lot, or occupy the front half of a lot, or either front quarter of an interior lot abutting two streets, provided; however, that this restriction shall not require any accessory building to be more than seventy-five (75) feet distant from any street lot line.
  • At least 10 feet from the side lot line, and no closer to the street side line than the house.
    Applies: Corner lots in an R district whose rear lot line borders the rear lot line of another lot.
    § 17.52.280 · code text
    Where the rear lot line of a corner lot in an R district abuts the rear lot line of another lot, no accessory building shall be nearer the street side lot line than the main building or in any case be located less than ten feet from the side lot line.
Distance from the house
  • At least 6 feet from any other building on the same lot.
    Applies: Detached accessory buildings in an R district.
    § 17.52.260 · code text
    No detached accessory building in an R district shall be located within six feet of any other building on the same lot, or have more than one story or a height in excess of fifteen (15) feet.

Who this affects

HomeownersContractorsDesigners

Frequently asked questions

How big can a shed or accessory building be in Alameda County?

In R districts, the county limits detached accessory buildings to one story and 15 feet, at least 6 feet from other buildings.

General information, not legal advice.

Ask about a specific Alameda County property

Ask GoCodebook how Alameda County's sheds, garages and other accessory structures rules apply to your situation and get an answer that cites the section.

Ask your question

More on building on your lot in Alameda County

All building on your lot rules in Alameda County

Fences and walls in Alameda County

Running a business from home in Alameda County

Grading and erosion control in Alameda County

Park and impact fees for new homes in Alameda County

Noise and construction hours in Alameda County

Home alarm permits and false alarms in Alameda County

Historic homes in Alameda County

Alameda County Municipal Code — full text