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Summary: This Tip explains how to establish an attached accessory dwelling unit (also called an AADU or mother-in-law unit). An AADU is a room or set of rooms designed and established by permit to be a separate dwelling unit. AADUs can be located in a single-family home in the Single Family (SF) 5000, SF7200, and SF9600 and Residential Small Lot (RSL) zones. In the RSL zone they can also be located in a principal dwelling of an apartment unit, carriage or cottage house, rowhouse, or townhouse. In the lowrise (LR) zones, AADUs can be located in a single-family home, rowhouse or townhouse unit.

Date Revised: 07/26/2022

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