Skip to Main Content View Text-Only

Development Services

From Concept to Construction

Phone: 503-823-7300


1900 SW 4th Ave, Portland, OR 97201

More Contact Info

Getting Started

A building permit is required for any addition to a single-family dwelling. Any project that changes the building envelope such as building a dormer or a new second story is considered an addition.

Depending on the scope of work, your project will most likely require electrical, plumbing and/or mechanical permits.

Your permit will be reviewed under provisions of the current Oregon Residential Specialty Code. View more information on building codes.

It is recommended to visit or call the Planning and Zoning staff (503) 823-7526 and Buildings staff (503) 823-7310 at the Development Services Center early in the planning of your project.

Checking your House’s History

Depending on the age of your house, we may have permit cards or microfilm on file that will show the history of permit activity for your house. It is important to verify that the “existing” finished attic or basement was permitted as such in the permit records, and not just through the county assessor’s office. Information found on is reported from the county's assessor's office, and may not match the building permit history. There is no grandfathering-in of these spaces, and to be considered living space, they would need to be legalized through the permit process.