Berkeley’s August 2026 information sheet distinguishes hillside from non-hillside lots and gives a separate treatment for some existing structures. Identify mapped status and bedroom count before comparing caps.
Local standards
The selected local standards are summarized in the Berkeley Forms ADUs — Information and FAQs, August 2026. For non-hillside lots, the City sheet lists a 1,200-square-foot maximum. On hillside lots, it lists 850 square feet for a studio or one-bedroom and 1,000 square feet for two or more bedrooms. The cited height examples also differ: 25 feet for detached ADUs generally and 20 feet for hillside detached units.
Confirm the applicable rule
The sheet describes a conversion route that may retain a lawfully existing envelope where the project makes no structural changes and satisfies life-safety conditions. That is not permission to enlarge or reconstruct a nonconforming building. Confirm current ordinance, mapped hillside status, bedrooms, existing permits, and fire/life-safety review. Zoning measurements do not by themselves establish fire separation, building-code compliance, utility capacity, or permit approval. For shared measurement methods, see the setback and separation guide and floor-area guide.
