Hayward, CA Accessory Structures: ADU Permits (2026)

Hayward's ADU rules are codified at HMC 10-1.2740 within Chapter 10 (Planning, Zoning, and Subdivisions), Article 1 (Zoning Ordinance), and were last updated to align with California Government Code 65852.2 and 65852.22. Review is strictly ministerial - no public hearing, no Planning Commission action, no design review, and no neighborhood notice (Gov. Code 65852.2(b)(1)). Applications are submitted through the Hayward Development Services Center / Permit Center on Watkins Street. Required submittals include a site plan, floor plans, elevations, Title 24 (California Energy Code) compliance documentation, and structural details. Hayward allows one ADU plus one JADU on a single-family lot, plus the primary dwelling - up to three units. Detached ADUs are limited to 1,200 sq ft, attached ADUs to 1,200 sq ft or 50% of the primary dwelling area (whichever is less), and JADUs are limited to 500 sq ft within an existing or proposed single-family home (Gov. Code 65852.22). Detached ADUs may be up to 16 ft tall on most lots and up to 18-25 ft on transit-adjacent lots per Gov. Code 65852.2(a)(1)(D)(i). Attached ADUs match the height of the primary dwelling up to 25 ft. State default 4 ft side and rear setbacks apply. AB 1033 (Gov. Code 65852.26) allows separate sale of ADUs as condominiums where adopted.