Before You Build in Alameda County, CA: Permit & Rule Checklist (2026)

Retaining walls over 4 feet in height (measured from bottom of footing to top) require a building permit and engineered plans in unincorporated Alameda County under the California Building Code.

Alameda County requires a building permit for fences over 7 feet tall in unincorporated areas. Fences under 7 feet generally do not need a permit but must comply with zoning height and setback limits.

Under California Civil Code 841 (Good Neighbor Fence Act), adjoining landowners in Alameda County share equal responsibility for reasonable costs of shared boundary fences unless one party shows the cost would be unjust.

CA Health and Safety Code 115920 requires pool enclosures at least 60 inches (5 feet) tall with self-closing, self-latching gates around residential pools and spas in Alameda County.

Alameda County Zoning Code §17.52.430 limits fences to 4 feet in required front yards and 6 feet in side and rear yards. A 2-foot limit applies within 30 feet of street intersections for sight visibility.

Hot tubs and spas deeper than 18 inches require permits and follow the same California Pool Safety Act fencing or locking-cover rules as pools; smaller spas follow electrical permit requirements.

Swimming pools and spas in unincorporated Alameda County require building, plumbing, and electrical permits and must comply with the California Building Code and Swimming Pool Safety Act (H&S 115920).

Unincorporated Alameda County enforces the California Swimming Pool Safety Act (Health & Safety Code §§115920-115929). Pools deeper than 18 inches require an enclosure at least 60 inches high, with gates that self-close and self-latch at 60+ inches above grade. New or remodeled pools must have at least two of seven approved drowning prevention features.

Unincorporated Alameda County applies California's Swimming Pool Safety Act (HSC 115920-115929) through Title 15 Chapter 15.08, which adopts the California Building and Residential Codes (2022 CRC Appendix AX). New or remodeled residential pools must have at least two of seven approved drowning-prevention features; any isolation barrier must be at least 60 inches tall.

Converting an attached or detached garage to an ADU in Alameda County is allowed ministerially under CA Gov Code 65852.2, with no replacement parking required for the ADU conversion.

Alameda County complies with California Government Code 65852.2 mandating ministerial ADU approval. ADUs up to 1,200 sqft for detached and JADUs up to 500 sqft are allowed on most residential lots.

Carports in Alameda County generally require a building permit and must meet residential setbacks. They may count toward lot coverage limits but are often allowed in setbacks with reduced requirements.

Unincorporated Alameda County treats a foundation tiny home as an Accessory Dwelling Unit under Title 17 Chapter 17.55 (Ordinance O-2024-32, Sept 2024). ADUs up to 1,200 sq ft are generally by-right under California Government Code Section 65852.2. A tiny house on wheels is classified by HCD as a recreational vehicle under ANSI A119.5 and is not a permanent dwelling.

Unincorporated Alameda County regulates sheds under Title 17 Section 17.52.260: a detached accessory building in any R district must be one story, no taller than 15 feet, and at least 6 feet from any other building on the lot. Title 15 adopts the California Residential Code; sheds 120 sq ft or less are generally permit-exempt under CRC R105.2.

Outdoor open burning is essentially prohibited in Alameda County under BAAQMD Regulation 5 Rules 3 and 6. Agricultural and prescribed burns require district permits and are limited to designated burn days. Residential yard waste burning is not allowed.

Fire pits allowed per California Fire Code with proper clearance. Prohibited on BAAQMD Spare the Air days if wood/solid fuel. Gas fire pits permitted.

East Bay Municipal Utility District (EBMUD) and Alameda County Water District (ACWD) enforce permanent water waste rules plus drought-stage restrictions. AB 1572 bans potable water on non-functional turf starting 2027.

Alameda County requires trimming of trees that obstruct public rights-of-way, block street-sign visibility, or interfere with utility lines. Protected heritage and native oak trees may require a permit before trimming.

Alameda County regulates removal of protected trees including heritage oaks, trees over specified diameters, and trees in designated natural resource areas. Permits are often required before removal on private property.