The City of Portland, Oregon
From Concept to Construction
1900 SW 4th Ave , Portland , OR 97201
Garage, Shed, Accessory Structures
Table of Contents
A building permit is required to build, demolish or alter any carport, garage or shed that is greater than 200 square feet in area (measured from the interior side of the exterior walls) or greater than 10 feet in height (measured from the finish floor level to the average height of the roof). Depending on the scope of work, your project may also require electrical, plumbing or mechanical permits.
A building permit is not required to construct a non-habitable accessory structure that is 200 square feet or less in area. However, a zoning permit could be required.
Your permit will be reviewed for compliance with the Portland Zoning Code, the Oregon Building Code and other local regulations.
- Applicable City and State Codes: Refer to the Codes page on the Bureau of Development Services (BDS) website.
- Portland’s applicable building code is the Oregon Residential Specialty Code. See the State Codes page for more information about this and other construction codes in effect.
- The Portland Zoning Code (City Title 33) includes use regulations and development standards, such as maximum building coverage and setbacks, and can be found on the Zoning Code page.
Our “New Users” tab is a good place to start for overall information about the permitting process.
Things to Consider when Planning your Project
(1) Location on the Lot
The Zoning Code, (City Title 33) includes regulations and development standards, such as maximum building coverage and setbacks, which will affect the size and placement of the structure on your property.
Visit Planning and Zoning staff at the Development Services Center or call (503) 823-7526 to determine your setbacks.
(2) Fire Walls and Fire Protection
The building code does not restrict placement of a structure on the lot, but it does require that if a structure is close to a property line, it must be constructed to a greater level of fire protection. Construction within three feet of a property line that you share with a neighbor (not a street or public alley) is required to be fire rated. See our handout on Eaves and Exterior Wall Protection.
If your accessory structure is a garage and it will be attached to, or within three feet of the house, then the interior walls of the garage must be covered with a layer of ½” gypsum board for additional fire protection. Any openings (such as doors and windows) within this distance may be required to be protected, depending on the configuration.
(3) Building a Garage
The City requires that a garage be accessed via a driveway. If you don’t currently have a driveway you will be required to put one in. The driveway will need to be paved if it is within 150’ of an improved public right-of-way. For additional information on paving surfaces, see Portland City Code, Title 24.45.020. The Zoning Code also includes requirements that may limit the width of a new driveway.
If your project requires construction in the public right-of-way, then the Portland Department of Transportation will review the project, and issue a separate transportation permit for this work as well. For more information about right-of-way requirements, contact the Portland Department of Transportation at (503) 823-7002.
(4) Cargo Containers
Sometimes, cargo containers can be used as accessory structures. These are challenging in that they too must meet all the requirements of the code.
(5) Residential Engineering
Your project must be designed to meet all structural requirements in the building code. The construction drawings must show how both gravity and lateral (wind and earthquake) loads will be resisted. Please see our page on Residential Engineering for more information on these requirements.
(6) Decommissioning a Septic Tank or Cesspool
When building an accessory structure, the septic tank/cesspool must be located if it exists.
- Visit the records staff at the Development Services Center to locate any old plumbing records showing a septic system/cesspool.
- If the septic system/cesspool is decommissioned, and within ten feet of the new structure, you must sign a disclaimer for on-site-sewage disposal system form.
- If the septic system/cesspool is within ten feet of the new structure, it will need to be decommissioned.
Call Environmental Soils staff at (503) 823-6892 for more information on decommissioning septic tanks and cesspools.
Permit fees are based on the fair market value of the work included in the permit.
Applying For My Permit
The following information must be submitted when applying for this type of permit. Since every project is unique, there may be some situations where you will be asked to provide additional information.
- Completed building permit application form
- Four sets of complete Construction Drawings, including Site, Architectural and Structural plans as listed in our Garages & Sheds Submittal Requirements handout
- If lot slope exceeds 20%, submit a geotechnical engineering report prepared by an engineer registered in the State of Oregon
- Erosion control plan (may be a part of the site plan) or completed simple site erosion control form, if the project will result in ground disturbing activity. Note:Erosion control measures shall be installed, even when a simple site erosion control form has been accepted
- Mitigation form and/or a stormwater plan if your project will add more than 500 square feet of impervious area
To submit for a permit, bring the above materials along with intake fees to the Development Services Center.
The Bureau of Development Services sells a “Residential Combination” permit package. This allows you to call for all inspections using just the Building Permit (RS) IVR number and pay for all the permits at one time. You will need to submit any trade (mechanical, electrical, and/or plumbing) application(s) signed either by you, if you are doing these portions of the work yourself, or by your licensed subcontractors. If you do not have your completed subcontractor forms when you are applying for your residential permit (RS) you will have to apply for trade permits separately from the building permit. Sub-contractors that you hire must be registered with the State of Oregon and carry the correct licenses in association with their trade.
Plan Review Process
Some simple permits can be reviewed and issued “over the counter” in the Development Services Center. You will meet individually with city staff from different departments. Each staff person will review your plans with you to verify that the proposed construction meets requirements. If information is missing or if corrections are needed, you will be asked to update your plans. In this case, another trip to the Permit Center may be needed.
If the project is more complex and a review cannot be completed over the counter, the plans will be taken in for further review. You will be sent a checksheet requesting any clarifications or corrections. For additional information on the review process, see the permitting process overview flowchart.
The bureaus/review groups that will check your project vary depending on the scope of work and may include:
- Planning and Zoning Review
- Life Safety Review
- Structural Review
- Residential Subsurface Evaluation—Site Development Review
- Bureau of Environmental Services
- Portland Department of Transportation
- Urban Forestry Review
When the last technical review is approved, your permit will be issued. If the permit can be approved “over the counter”, you would pay the full amount at that time. If the permit is taken in for review, you would pay a partial amount covering the review fees, and the balance of the fees when it is ready to pick up. You will be contacted and given your final fee total when your permit is ready.
The blue inspection card lists all the inspections you will likely need during your construction project, and what work needs to be done first.