Find out if you need a permit for a retaining wall. Apply for a residential retaining wall permit in the City of Portland. Get all required applications and helpful forms for a retaining wall permit. Then, apply online for a retaining wall residential permit.
A building permit is required when constructing a retaining wall that:
- is more than four (4) feet high, measured from the bottom of the footing to the top of the wall.
- supports a surcharge. A surcharge is an additional load, beyond the normal weight of a level earth backfill is to holding back.
If a building permit is not needed, you may need a zoning permit - contact Planning and Zoning with questions.
For complex sites or if slope stabilization is needed, you may need a Site Development permit - contact Site Development with questions.
Required applications and important forms for retaining wall permits
Step 1: Research what you need for a residential retaining wall
Codes and Rules
Residential Retaining walls that require building permits are regulated by the following codes:
- Oregon Residential Specialty Code
- Title 33 Zoning Code
City and State Codes and Rules has the current code.
Permit fees are based on the type of permit, the work proposed, the valuation of the work, and the staff that need to review the work. Get permit fee information.
Step 2: What you need to get a residential retaining wall permit
In addition to the building permit application, you will need a site plan and engineering information to get your permit. An engineer registered in the State of Oregon must provide stamped drawings and calculations for wall(s) over four feet tall.
Since every project is unique, there may be some situations where you will be asked to provide additional information.
Site plan (Scale site plans to most appropriate scale, e.g. 1”=10’ or 1/4”=1’)
- Property lines, with dimensions
- Adjacent streets and any easements
- Property address and R number
- North arrow
- Distance between buildings and between buildings and property lines
- Dimensions and area (in square feet) of any proposed paving. (If your project will add more than 500 square feet of impervious area you will need to provide a mitigation form and/or a stormwater plan)
- Dimensions and placement of the new retaining wall on the lot
Structural Engineer stamped drawings and calculations
Design of retaining walls over four feet tall should include a site sketch consistent with the site plan submitted with the application.
Or, instead of a site sketch in the calculation package, the engineer may submit a letter stating that the calculations were prepared for the site as shown on the submitted site plan prepared by others.
Where the retaining wall influences the loads on a building, the engineering evaluation should address the effect of the loads imposed onto the building. In all cases, and especially where tiered retaining walls are proposed, the analysis shall include complete free-body diagrams of the retaining walls showing all loads acting on the retaining wall system and all loads used to resist the applied forces. The calculations shall clearly state all assumptions and list the soil design parameters used in the design.
Some sites may require a geotechnical report.
Site development review
Depending upon the placement of the building or structure, the following items must be addressed in evaluation and analysis of the design:
- Slope and retaining wall drainage
- Erosion control
- Potential for shallow failures
- Potential soil creep
- Potential settlement
- Effect of surcharge loads such as new building and/or structure footings
- Protection of adjacent property and existing building during construction
For more information contact Site Development & Septic Review.
If your project requires construction in the public right-of-way, 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 Transportation at (503) 823-7002.
Make sure that the design of your retaining wall does not result in a section of the foundation or specifically the “toe” (the outside points of each leg of a structural angle) needing to be placed off of your property.
Soils and/or structural special inspections
Soils special inspections and/or structural special inspections may be required prior or during the construction of your retaining wall.
Soils special inspections may be required for work that includes foundation work of a more complicated nature such as piling, or foundations on steep slopes or large jobs; and retaining walls, landslide slope remediation work or other earthwork-related work. Soils special inspection is performed by the geotechnical engineer of record and/or an approved testing agency and is hired for this purpose by the (permit holder) property owner. View more information on special inspections in the related webpage.
Step 3: How to apply for a residential retaining wall building permit
To apply for a permit, submit the completed building permit application and site, architectural and structural plans (for the area of proposed work and areas affected by such work) and engineering calculations.
Get step-by-step instructions submitting a permit application request online or in-person.
For most projects, electronic plans are submitted through the Single PDF process. Large scale projects such as commercial new construction are submitted though PDX E-plans and ProjectDox. If you are unable to create electronic plans, please call us and we will work with you.
Step 4: Plan review process and checksheets
After you pay intake fees, your project will be under review. The bureaus/review groups that will check a typical retaining wall project are:
- Planning and Zoning Review
- Life Safety Review
- Structural Review
- Site Development Review
- Environmental Services
If a reviewer needs more information, they will send a checksheet to the applicant requesting corrections or more information. The plans will need to be updated and re-submitted with the checksheet response.
The permit review process webpage has more information. You can check the status of the permit review on Portland Maps permit/case search.
Step 5: Getting your permit
When the last technical review is approved, your permit will be pre-issued. Pre-issuance is the last permit check. This step ensures all required reviews took place, all required approval stamps are on the plans, and the fees are charged correctly. You will be contacted when your permit is ready, and notified of your final fee total. Instructions will be given on how to get your approved permit and pay your fees. Your permit is not issued until all fees are paid.
Find out if a permit application is still under review, in process or about to be issued.
Step 6: Start building and get ready for inspection
The inspection card lists all the inspections you will likely need during your construction project, and what work needs to be done first.
Once your building permit is issued, erosion control measures and sometimes tree protection measures must be installed, inspected and approved prior to beginning any further ground-disturbing activities.
All permits need a final approval inspection to be complete.
Step 7: Residential inspections, results and corrections
To schedule an inspection, call the automated inspection request line. You will need your IVR or permit number and the three digit code for the inspection.
Get the results of the inspection on Portland Maps permit/case search the next day.
Not approved - there are some reasons why the work did not get approved:
- no access - the inspector may not have been able to inspect the work
- incomplete work
- code violations
The inspector will list the corrections needed on the inspection report.
Call for a reinspection after making the corrections. Use the same three digit inspection code.
If you make the corrections the same day wait until 5 pm to request a reinspection. The inspector needs to enter their results before you can schedule the reinspection.
There is a reinspection fee charged for more than one reinspection for a single issue.
Contact residential inspectors
If you have questions before your inspection, you can talk to an inspector. The 1 & 2 family inspector area map list the inspector's name, area, and phone number.
Because of vacation or illness, your inspector may be different than the one listed on the map. If you have questions after your inspection, find out which inspector to call. Their contact information will be on the inspection results and on Portland maps.