Construction Permit - Addition or Alteration

What Is It?

You need a construction permit to remodel or add onto your building, whether it is a single-family house, multifamily building, or a commercial or industrial building. New structures that are accessory to an existing house, such as a backyard cottage, are considered additions.

  • An addition involves changes to the outside of the building, such as adding floor area
  • A remodel (also known as an alteration) is when you make changes to the building’s interior, like moving non-structural walls

Examples of common projects are adding a second floor, creating another living unit in your home, or remodeling a building for a new business.

How Much Does It Cost?

Fees are based on the value of your project. You pay approximately 75 percent of your fee when you submit your plans and the rest when you pick up your permit. Use our fee estimator to estimate how much your permit will cost. We will also charge hourly fees for certain reviews, such as drainage and geotechnical; see our Fee Subtitle for details.

How Long Does It Take?

We try to finish our initial review of simple permit applications in 2-3 weeks and complex permits in 8 weeks.

How long it takes to get the final permit depends on how complex your project is and how many corrections, if any, you need to make.

If you have a small project, you may be able to get a same-day permit called a subject-to-field-inspection permit.

Steps to Get Your Permit

Get your property information. Find property information to help you plan your project.

Determine restrictions to your project. Research our codes to determine building size limits and construction and life / safety requirements.

Research Stormwater Code requirements. We may require a drainage review of your project. You need to determine whether stormwater requirements apply to your project to submit a complete and accurate application. 

Find incentives for your project. Research the City's different incentives that might apply to your project.

Determine if you need a land use permit. If your project is not a single-family building, you might need a Land Use / Master Use Permit. We need 4 to 8 months (or more) to review land use permits, which must be submitted before you submit your construction permit application.

Attend a coaching session. We offer 20 minutes of free coaching at the Applicant Services Center to answer drainage, land use, geotechnical or construction permit questions. If you need a longer coaching session, we offer one-hour sessions for a fee.

Start your application. Complete the Building & Land Use Pre-Application online using the Seattle Services Portal. You will need to upload a site plan and a complete legal description for your site.

Request a pre-application site visit. You  need a pre-application site visit if you will disturb more than 750 square feet of land or disturb any land on a site with an environmentally critical area (other than liquefaction or peat-settlement prone areas). Request a pre-application site visit online through the Seattle Services Portal. You'll receive an email once we have added the pre-application site visit (PASV) fees to your project. After you have paid the fee, we will perform the inspection.

Request a pre-submittal conference (optional). We recommend pre-submittal conferences for very complex projects, including buildings with unusual structural systems, substantial alterations, or work in environmentally critical areas or shorelines. You will need to pay a minimum conference fee of 1.5 hours of staff time. We might charge additional hourly fees based on the number of City staff attending the conference, and the amount of follow-up time required.

Apply for exemptions. You may need an exemption if your project is located in an environmentally critical area or near the shoreline.

Prepare your plans. Plans should be to scale and easy to read.

Fill out forms.

Coordinate with other agencies. You may need permits or approvals from other agencies. These are the most common agencies you may need to work with for your permit type:

Get your project screened. We screen your application to make sure it is ready to submit. Screening is available on a walk-in basis at the Applicant Services Center or through your Seattle Services Portal. You may schedule an appointment without screening if you are a consistently prepared applicant with a rating of 80 percent or better. 

Schedule an intake appointment. Schedule an electronic intake appointment through the Seattle Services Portal. You must upload all application documents by 7:00 a.m. on the day of your appointment. We may contact you that day for more information.

Pay fees. Approximately 75 percent of your permit fees are due at intake. The fees are calculated based on your project value.

Make corrections and resubmit your plans. Once all of our reviews are done, you will receive an email telling you that corrected and/or additional documents can be uploaded into your portal. Your project may require multiple correction rounds before our reviews are complete.

Pay final fees. We will notify you if you need to pay any final fees before we issue your permit.

Print your permit. We will notify you when we have issued your permit and the documents are available in your Seattle Services Portal. Print the permit and approved plan set.

Display your permit. Place your permit in a visible location on the project site.

Get related permits. You may need to get additional permits or approvals from other departments.

Request an inspection. See the construction inspections page for when to call us and how to schedule your inspection.

Receive your certificate of occupancy. You only need a certificate of occupancy if you have changed the use of, or number of residences in, your building. Single-family and duplex projects never need a certificate of occupancy; you just need a final "approved" inspection for your project. 

Close your permit. Your permit information will be archived in our electronic document management system.