County directory

Alameda County ADU rules

Each place name links to that city or county's own ADU page. Places with a 'See our rules summary' button also have our plain-language summary of the local ADU rules, with sources. Each place below says whether we show local rules or California state rules.

Places in Alameda County

Alameda (opens the government site in a new tab)
Showing California state rules because a local rule change is pending
A local rule change is pending. The City introduced changes to its ADU rules (Alameda Municipal Code 30-5.18) on September 15, 2026, and the adopted text could not be confirmed when this research summary was prepared. We'll add the new local rules after they take effect and we've reviewed them.
Albany (opens the government site in a new tab)
Showing California state rules because Albany's local rules may conflict with state law or are being challenged
We show the state rules for an ADU section that cites the old state ADU law, a two-detached-ADU limit on multifamily lots, and an owner-occupancy rule for every junior ADU. Check with Albany about how it handles this today.
Berkeley (opens the government site in a new tab)See our rules summary
Showing California state rules, plus Berkeley details
The size, setback, height, and parking figures are California state rules. The Berkeley section lists the local details we have on file, like plans, forms, and contacts.
Dublin (opens the government site in a new tab)See our rules summary
Showing California state rules, plus Dublin details
The size, setback, height, and parking figures are California state rules. The Dublin section lists the local details we have on file, like plans, forms, and contacts.
Emeryville (opens the government site in a new tab)See our rules summary
Showing Emeryville city rules
These are Emeryville's own ADU rules on file, shown with the California state rules they build on. Each item says which is which.
Where a Emeryville rule may conflict with state law or is being challenged, we show the California state rule instead. This covers limits on which zones allow ADUs and junior ADUs, and a two-detached-ADU limit on lots with existing multifamily buildings.
Fremont (opens the government site in a new tab)See our rules summary
Showing California state rules, plus Fremont details
The size, setback, height, and parking figures are California state rules. The Fremont section lists the local details we have on file, like plans, forms, and contacts.
Hayward (opens the government site in a new tab)See our rules summary
Showing California state rules, plus Hayward details
The size, setback, height, and parking figures are California state rules. The Hayward section lists the local details we have on file, like plans, forms, and contacts.
Livermore (opens the government site in a new tab)See our rules summary
Showing Livermore city rules
These are Livermore's own ADU rules on file, shown with the California state rules they build on. Each item says which is which.
Where a Livermore rule may conflict with state law or is being challenged, we show the California state rule instead. This covers owner-occupancy rules for junior ADUs, a rule that ADUs sit behind the main home, a 15-foot front setback, lot coverage and floor area limits, and a ban on attached ADUs at historic properties.
Newark (opens the government site in a new tab)See our rules summary
Showing California state rules because Newark's local rules may conflict with state law or are being challenged
The size, setback, height, and parking figures are California state rules. The Newark section lists the local details we have on file, like plans, forms, and contacts.
Where a Newark rule may conflict with state law or is being challenged, we show the California state rule instead. This covers a design review step for second-story ADUs taller than 16 feet.
Oakland (opens the government site in a new tab)See our rules summary
Showing Oakland city rules
These are Oakland's own ADU rules on file, shown with the California state rules they build on. Each item says which is which.
Where a Oakland rule may conflict with state law or is being challenged, we show the California state rule instead. This covers limits on ADUs in the S-9 fire safety zone and parking for converted ADUs.
Piedmont (opens the government site in a new tab)
Showing California state rules because Piedmont's local rules may conflict with state law or are being challenged
We show the state rules for ADU rules (Ordinance 777, January 2025) that a January 2026 state housing department letter found do not meet state ADU law. Check with Piedmont about how it handles this today.
Pleasanton (opens the government site in a new tab)See our rules summary
Showing California state rules, plus Pleasanton details
The size, setback, height, and parking figures are California state rules. The Pleasanton section lists the local details we have on file, like plans, forms, and contacts.
San Leandro (opens the government site in a new tab)See our rules summary
Showing California state rules because San Leandro's local rules may conflict with state law or are being challenged
The size, setback, height, and parking figures are California state rules. The San Leandro section lists the local details we have on file, like plans, forms, and contacts.
Where a San Leandro rule may conflict with state law or is being challenged, we show the California state rule instead. This covers a replacement parking rule when a garage is turned into a junior ADU.
Union City (planning page) (opens the government site in a new tab)See our rules summary
Showing Union City city rules
These are Union City's own ADU rules on file, shown with the California state rules they build on. Each item says which is which.
Where a Union City rule may conflict with state law or is being challenged, we show the California state rule instead. This covers an owner-occupancy rule for every junior ADU.
Unincorporated Alameda County (opens the government site in a new tab)See our rules summary
Showing Alameda County rules
These are Alameda County's own ADU rules on file, shown with the California state rules they build on. Each item says which is which.
Where a Alameda County rule may conflict with state law or is being challenged, we show the California state rule instead. This covers a two-detached-ADU limit on multifamily lots in one part of the rules, a size cap on attached ADUs with two or more bedrooms, and design guidelines for larger ADUs.

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