Attic, Basement or Garage Conversion Residential Building Permits

Information on permits and inspections needed to convert an attic, basement or garage. Get all required forms for an attic, basement or garage remodel. Find information on the permit process and checking permit history before you add a room or add a bedroom in the City of Portland.

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A building permit is required to convert attics, basements or garages to living or habitable space. Your project may also require electrical, plumbing or mechanical permits.  If you are creating a new dwelling unit, visit the Apply for an Accessory Dwelling Unit page.  If you are converting space by adding dormers or a second floor, visit the Apply for a dormer or second story permit. 

Required forms and important handouts for a residential conversion to living space permit

The following information must be submitted when applying for a conversion permit. Since every project is unique, there may be some situations where you will be asked to provide more information. More detailed information visit our Conversion to Habitable Space Submittal Requirements.

Step 1: Research your property and what you need for your project

Code and rules

Permits are reviewed under multiple city and state codes including: 

When converting unfinished areas to living space, the code requires that the remodeled area conform to current code. The Bureau of Development Services has established alternative standards for conversion projects explained in Converting Attics, Basements and Garages to Living Space.

How to check the permit history for a house 

Depending on the age of your house, we may have inspection cards or microfilmed plans that show the permit history for your house. It is important to verify the permit records, and not rely on the tax information from the county assessor’s office. If "existing” finished attic or basement was not permitted, it will need to be legalized through a new permit. To be considered living space, you would need to submit for the same conversion permits as if the work was not already done.  

Some records are available online, visit our Public Records Access page.

Evaluating existing space

Unfinished areas may not meet current building code requirements for living space. This includes: 

  • Ceiling height
  • Stairs
  • Emergency Egress Windows
  • Insulation and Ventilation

These conditions could make it expensive, difficult or even impossible for you to convert into living space. The Bureau of Development Services allows special standards for existing situations.  

Adding a bathroom to an unfinished basement

You can add a bathroom in the basement and leave the basement unfinished. In this case, the basement does not have to comply with all conversion standards.  The ceiling height in the bathroom must follow Brochure #9, Converting Attics, Basements and Garages to Living Space. The stair to the basement and a three foot wide path through the basement from the stair must meet the headroom and other dimensional requirements listed. The other requirements listed (including exterior wall insulation, storm windows and egress windows) are not required if no other habitable space is proposed in the basement.

Additional sinks and kitchens

 If your project will add a sink outside of a bathroom or kitchen, you may need a covenant. The "Covenant for a Sink Outside of the Primary Kitchen, Bathroom or Laundry Room inside a Single-Family Dwelling" is also called a 2nd sink covenant. This document affirms the addition does not create another dwelling unit. It also states the structure is still be a single-family dwelling. Contact Planning and Zoning staff with questions. If required, this document must be recorded with Multnomah County before your permit can be issued. 

If your final project will include both a kitchen and a bathroom it may need to be permitted as an Additional Dwelling Unit (ADU).  ADUs can be used independently of the remainder of the dwelling.  Building Code requirements define a “Dwelling Unit” as “a single unit providing complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation.” The permit requirements for an ADU are different. For questions about what makes a dwelling unit, contact Building Life Safety Plan Review. 

Attic and dormer additions

If converting attic space to living space would mean raising the roof, the zoning code height regulations may affect your project. If you are adding dormers or another story, visit apply for a dormer or second story addition for requirements.

Combination permits

The Bureau of Development Services sells a "Residential Combination" permit package. This allows you to call for all inspections using one Building Permit (RS) IVR number. You can also pay for all the permits at one time. If you choose a combination permit, you will need to submit the trade (mechanical, electrical, and/or plumbing) applications with your plans. If you are hiring subcontractors to do the trade work, they must sign their trade permit application.  

Contractors must have a license to work in Oregon. The Oregon Construction Contractors Board (CCB) issues licenses to contractors. The permit application and their company materials must list the license number. Need help finding a contractor? The CCB website has good tips on how to search for one.  Plumbing and Electrical contractors have additional license requirements.  

If you are doing the work yourself, then you can sign the trade permit applications. You can only do the electrical work if you own and occupy the home and are not planning on selling or renting within 6 months.  

Engineering calculations

When the scope of work will change the structural load, it is important that you submit engineering calculations that show the continuity of the load path from floors or other affected members all the way to the foundation.

You must determine if the existing attic floor structure is strong enough to carry the additional weight of people and furniture. It is very common that when tracing floor loads from the converted attic, it is the beam in the basement that will be overstressed. Situations like this are required to be resolved as part of the permit application.  For more information, visit the Residential Engineering webpage. 


If your house is located in a floodplain, there are restrictions that may limit your ability to add or to significantly improve your house. The work may require retrofitting your house to be flood resistant. Flood plain information is available on Portland Maps Flood Hazard gallery.  If the property is located in a flood plain, talk to Site Development & Septic Review in the early stages for what is needed. 

Garage conversions

  • Parking: You will need to show how you will provide the required parking space. Parking in your driveway alone may not meet the parking requirement.
  • Setbacks: If you want to convert a detached garage to living space, it may not meet setback requirements.  The zoning code may not allow living space to in the setback areas, even if it allows the garage to be in that location.
  • Structural: A detached garage may not have been built to the building code standards for living space. You will need to upgrade any structural deficiencies.  Some garages may not have needed a permit because it was previously exempt due to its use and size. In this case,the garage will need to have all structural elements submitted and reviewed as part of the conversion to living space.
  • Right of Way: If your project requires a new driveway or construction in the public right-of-way, then Portland Department of Transportation (PBOT) will review the project. They may require separate transportation permit for this work as well. For more information about right-of-way requirements, contact the PBOT at (503) 823-7002.

Permit fees

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. 

Step 2: What you need for a conversion to living space permit

You will need a completed building permit application, a site plan, and architectural plans.  Review the plan drawings requirements:

  • Drawings, drawn to scale where necessary to verify compliance with code.
  • Drawings may be handwritten/drawn if clear and legible. Text or note shall be in print.
  • Minimum drawing size: 11x17. All required information is to be clear and legible. Minimum printed text is to be 3/32” or the equivalent 12-point font.
  • Cannot use professional's drawings without the permission of the professional who signed the original drawings. For example, an architect’s stamped plan set cannot be used without their permission.

Depending on the scope of work, you may also need structural calculations. 

If your project qualifies as a Major Residential Alteration and Addition, there are additional requirements including a delay period and notification to neighbors and neighborhood associations. See the MRAA page for more detail on these requirements.

If you are applying for a combination permit you will also need to submit the trade permit applications (Electrical, Mechanical, and Plumbing).

Each project is unique and you may be asked for additional information.

Step 3: How to submit your conversion to living space permit application 

Schedule an a Building Permit Intake Appointment

If you are unable to create electronic plans yourself, please call us and we will work with you.

During your appointment time, our staff will guide you through uploading your plans using a secure link we will provide. To file a permit application, you must upload a completed application and all submittal materials. 

Step 4: Plan review process and checksheets

Different departments will review your plans to verify that the proposed work meets requirements. 

The bureaus/review groups that will check a typical conversion project are (in order):

  • Planning and Zoning
  • Life Safety Review
  • Structural Review
  • Site Development Review
  • Water Bureau, depending on the number of new fixtures in the structure
  • Urban Forestry Review

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 related permit review process webpage has more information.  You can check the status of the permit review on Portland Maps permit/case search.

Step 5: Permit issuance

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. 

Step 6: Start building and get ready for inspections

The inspection card lists all the inspections you will likely need during your construction project, and what work needs to be done first.  Anything having to do with walls, floors, ceilings, stairs, roofs is structural.  These need to be inspected before they are covered in any way, or before pouring any concrete.

For combination permits including electrical, mechanical and plumbing, visit the trade permit pages for information on the order of inspections. 

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.


Building Code Plan Review

Development Services

phone number503-823-1456

Monday through Friday from 8 am - 5 pm. Leave a message with detailed information.

General Inquiries

Development Services

phone number503-823-7300

Monday through Friday from 8 am - 5 pm. Leave a message with detailed information.

Permitting General Information

Development Services

Requests for Inspection and Inspection Results

Development Services

phone number503-823-7000

Automated Line - Requires an IVR or permit number

Residential Inspections

Development Services

phone number503-823-7388

Monday through Friday from 8:15 am - 3:45 pm. Leave a message with detailed information.

fax number503-823-7693

Schedule a Building Permit Application Appointment

Development Services

phone number503-823-4092

Call this number to leave a message. If you would like to schedule an intake appointment for a building permit, development review permit or zoning permit, click on the link below.