Attic, Basement, or Garage Conversion

Information on permits and inspections needed to convert an attic, basement or garage. Get all forms and apply for a permit online to remodel an attic, finish a basement or do a garage remodel. Find the code guide and check the permit history before you add a room or add a bedroom.
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The City of Portland welcomes the opportunity to work with you on your attic, basement or garage conversion permit. Learn more about what's required with your permit application. You can also schedule an appointment to discuss your project.

You'll need a building permit for this project 

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're converting space by adding dormers or a second floor, visit Residential Addition Permits Dormer or Upper Floor Permits

Learn about ADU permits 

If you plan to use the converted space as an accessory dwelling unit (ADU), visit the Accessory Dwelling Unit Permit webpage.

What you need for a conversion to living space permit completed application 

You will need a completed building permit application, a site plan (often called a plot plan) and architectural plans. Please carefully read the submittal requirements. The requirements explain what you must include to have a completed application and include links to other forms like the building permit application.

Review the submittal requirements to learn more about what's required with your application:

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 (MRAA), there are additional requirements including a delay period and notification to neighbors and neighborhood associations. See the MRAA webpage 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.

Who can do the work

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 a homeowner 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. The State of Oregon has some helpful information for homeowners: 

Building permit application, forms and information for a residential conversion to living space permit

The following information is part of the application. This is everything you might need when applying for a permit to convert an attic, basement or garage. Since every project is unique, there may be some situations where you will be asked to provide additional information. Things you need to apply for this permit may include some or all of the following.

If you aren't sure what you need, contact Permitting Services. You might also want to read our step-by-step guide for completing a building permit application

Conversion to living space permit forms and information include: 

Architectural plans 

Building permit application 

Completeness Checklist: Residential Additions and Alterations for Life Safety and Structural Review (Fillable)

Download the Word document and save a copy to use this form:

Erosion concerns sign 

International Residential Code and OR specialty code ORSC Chapter 3

This code guide sets minimum standards for changing a space to habitable space. It also sets minimum standards for changes in the use of an existing habitable space:

Residential water service application 

If project will result in more than 3 bathrooms on site:

Residential Water Service Application

Sample floor plan

Sample site plan

Submittal requirements for converting an attic, basement or garage 

Structural plans and calculations (if applicable)

When you need a building permit and trade permits (combination permits)

Step 1: Research your property and what you need to convert your attic, basement or garage

Codes and rules

Permits are reviewed under multiple city and state codes including: 

Other codes may apply based on the scope of work. The City and State Codes, Administrative Rules, Code Guides and Program Guides web page has the codes, administrative rules, code guides and program guides.

When converting unfinished areas to living space, the code requires that the remodeled area conform to current code. Development Services has set alternative standards for conversion projects explained in this brochure: 

This code guide explains the details of the alternative code requirements:

How to check the permit history for a house 

Depending on the age of your house, we may have inspection cards or 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 the How to Request Public Property Records webpage.

Evaluating existing space

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

  • Ceiling height
  • Stairs
  • Emergency egress or emergency exit 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. 

This code guide explains the alternative code requirements: 

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 or exit windows) are not required if no other habitable space is proposed in the basement.

If your project is limited to adding a bathroom, with no other conversion proposed, you may be able to use the Simple Bathroom Permit process.

Add sinks or add a kitchen 

Kitchen that is not closed off from the main kitchen

If your final project adds a kitchen that is not closed off from the main kitchen in the house, it may qualify as an “Accessory Kitchen”. This situation would not be considered as creating a separate dwelling unit. 

An accessory kitchen covenant is required to be recorded before the permit could be issued.

To find out if your project qualifies visit the following document: 

Non-accessory kitchen and a bathroom

If your final project will include both a non-accessory kitchen and a bathroom it may need to be permitted as an Accessory 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 General Inquiries. 

Attic conversion or dormer additions: adding a bedroom or extra room

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.

Get a building permit and trade permits (combination permits)

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.  

Engineering calculations for attic conversion

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 Structural 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 Permits and Inspections in the early stages for what is needed. 

Converting a garage

  • Parking: Off-street parking is not required in the City of Portland. If you are removing a parking space in a garage and want to keep your driveway, you will need to show how you will provide a parking space outside of required setbacks. Parking in your driveway alone may not meet the location requirement.
  • 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.
  • Fire separation: If an exterior wall of a garage being converted to living space is within 3’ of a property line (except for a property line along a public right of way), it will require fire-rated construction. There may also be limitations on the allowed eave or rake projections from that wall. Review the Eaves and Exterior Wall Protection guide:  
  • Right of Way: If your project requires a new driveway or construction in the public right-of-way, then 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 Transportation 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 1b: Still need help? Schedule a free 15-minute appointment 

This is an optional step. If you still need help, we are here for you if you have questions about the information and materials you need to apply. You can schedule a free 15-minute appointment with any of these reviewers to discuss attic, basement or garage conversion permits:

  • Meet with a City Planner to receive information about planning and Zoning and Tree Code requirements that apply to your property. 
  • Meet with a Building Code and Engineering Reviewer to get help with building code and engineering requirements. 
  • Meet with a Permit Technician if you have questions about the permit process or if you need help with application requirements.
  • Meet with a Water expert tofind out if your project requires you to increase the size of your existing water meter. 

If you need help, these are experts we recommend you meet with about attic, basement or garage conversion permits. Not all review groups are listed. The groups listed above will help get you started. 

Step 2: How to apply for a conversion to living space permit 

You can submit your permit application request online using Development Hub PDXRead step-by-step instructions for submitting a permit application request online or in person. 

For most projects, electronic plans are submitted through the Single PDF process. Large projects such as commercial new construction are submitted though PDX E-plans and ProjectDox.

If you need to submit paper plans, you can set up an appointment to pick up plans or drop off plans in person. Or, please call us and we will work with you. 

Step 3: Plan review process and making corrections to an application (checksheets)

You can check the status of a permit review on Portland Maps permit/case search. Many people might review a single permit. The Permit Review Process webpage has more information about the groups who review permits. 

A checksheet is sent to the applicant when a reviewer needs additional information or a correction has to be made to the plans. Read more about how to send us corrections and how to prepare corrected paper plans.

Step 4: Get your attic, basement or garage conversion permit 

We'll contact you when your permit is ready, and notify you about any fees due. You'll get instructions for how to get your approved permit and pay your fees. Your permit is not issued until all fees are paid. Read more about the pre-issuance process.

Step 5: 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 6: Residential inspections, results and corrections

To schedule an inspection, call the automated Requests for Inspections phone number. You'll 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.

Read more about why work does not get approved and how to schedule a reinspection.

Contact residential inspectors about your permit inspections

If you have questions before or after your inspection, you can talk to an inspector.

More information about converting attics, basements and garages to living space


General Inquiries

Development Services
phone number503-823-7300Our front desk team will be available to answer Monday through Friday from 8 a.m. to 5 p.m. Please leave a message if you call outside of those hours.
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Requests for Inspection

Development Services
phone number503-823-7000Automated Line - Requires an IVR or permit number
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Residential Inspections

Development Services
phone number503-823-7388Monday through Friday from 8:15 a.m. to 3:45 p.m.
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fax number503-823-7693