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Summary: This Tip explains how to establish a Detached Accessory Dwelling Unit (DADU), also known as a backyard cottage, or mother-in-law unit. A DADU is a type of accessory dwelling unit consisting of a room or set of rooms designed and established by permit to be a separate dwelling unit. DADUs share a lot with a single-family home in SF5000, SF7200, and SF9600 zones, any principal unit in an RSL zone, or with a single-family home, rowhouse or townhouse in a lowrise zone.

Date Revised: 02/25/2021

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