Property & Building Use

See also: New BusinessesMother-in-Law Units

What Is It?

A black man with short hair and a trim beard thinking about buying a building to change the use to a new business.Changing Property or Building Use
You may need to record a change in the use of your property or building if its use is different than in the past. For example, if you’re opening a new restaurant in a space that previously held a retail store, or if you’re creating a new home or space within an existing building (such as a mother-in-law unit or art studio), you need to change your property’s use.

Establishing Property or Building Use
We require that you change your property’s or building’s use when its use was not previously recorded but should have been. For example, if a triplex structure exists on property zoned for single-family residences, and a permit for the triplex was never obtained, you need to establish the use.

What Permits Do You Need?

You need a construction permit to establish use to change or establish your property’s or building’s use. If you’re also renovating or remodeling your building, you can often change your use as part of your addition / alteration permit without getting a separate permit to establish use.

Research the Code

You should research our Seattle Municipal Code (SMC), also known as the Land Use Code, to determine if we allow your new use. This is especially important before you sign a lease to open a business. We detail the uses we allow in each of our land use zones. When establishing use, we apply the use allowed by the land use code when the building was originally constructed. Our land use technical resource lead in the Applicant Services Center can help answer your zoning questions.

You should also research the Seattle Existing Building Code (SEBC) for the use allowed by the current code, for a change in use, or for the use allowed at the time of construction, for establishing use. The allowed use depends on the building’s type of construction, exiting, fire protection construction, and sprinklers. If you change or establish use, the change could be considered a “substantial alteration” under the SEBC. For example, if the new use involves an occupancy that is considered more hazardous. If it does, you should schedule a pre-submittal conference before you submit your application for building permit.

You should also research your property to find out how we classify the present use of your property. You can find your property’s use in your certificate of occupancy or in its permitting history. Older records may only be available in the microfilm library at our Applicant Services Center.

Should You Hire a Professional?

You should hire a professional to prepare your plans. However, we do not require your drawings be stamped by a professional architect or engineer if your project is a single-family house and is subject to the Seattle Residential Code.

Construction and Inspections

Nathan Torgelson, Director
Address: 700 5th Ave, Suite 2000, Seattle, WA, 98104
Mailing Address: P.O. Box 34019, Seattle, WA, 98124-4019
Phone: (206) 684-8600
Phone Alt: Violation Complaint Line: (206) 615-0808
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SDCI issues land use, construction, and trade permits, conducts construction and housing-related inspections, ensures compliance with our codes, and regulates rental rules. SDCI is committed to an antiracist workplace and to addressing racism through our work in the community.