ADU Handbook

ADU Handbook - Updated March 2026

In December 2025, HCD added an Addendum at the end of the ADU Handbook that summarizes changes to State ADU Law in effect on January 1, 2026.

Accessory Dwelling Unit Handbook (PDF)

Manual de Unidades de Vivienda Accesoria (PDF)

ĐƠN VỊ NHÀ PHỤ THUỘC SỔ TAY (PDF)

附屬住宅單元 手冊 (PDF)

附属住宅单元 手册 (PDF)

View the 2025 Accessory Dwelling Unit Handbook Webinar.

View the 2026 Accessory Dwelling Unit Handbook Webinar.

For additional assistance, please contact HCD’s ADU team.