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The Department of Planning and Building Permit Center is open by appointment only for limited building permit intake, correction returns/pick-up and to schedule virtual meetings. To submit electronic Building Permit or Land Use Permit Applications please visit  our website.

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Planning & Building

County of San Luis Obispo

Accessory Dwelling Unit

The following information will be helpful when trying to build an Accessory Dwelling Unit for your home or multi-family building.


Coastal Accessory Dwelling Unit

This guide serves to help you determine whether an accessory dwelling unit (“ADU”) can be established on a parcel or lot (“site”) under the State ADU Law (Coastal Zone).

Inland Accessory Dwelling Unit

This guide serves to help you determine whether an accessory dwelling unit (“ADU”) can be established on a parcel or lot (“site”) under the County ADU Ordinance (Inland Areas).

Movable Tiny Houses

Movable tiny houses are not allowed to be used outside of approved campgrounds or recreational vehicle parks in the unincorporated areas of San Luis Obispo County, as they do not comply with building codes. However, tiny houses built on permanent foundation are allowed, and are subject to obtaining County building permits.