Mechanical Permit

What Is It?

A mechanical permit enables you to install new mechanical equipment such as heating, venting, and air conditioning (HVAC) equipment and kitchen hood exhaust systems. It does not enable you to install plumbing, sprinklers, gas lines, refrigeration, and boiler pressure vessels; these all require a separate permit. See Tip 415, Applicant Responsibilities and Plan Requirements for Mechanical Permits, for information about the types of mechanical permits and submittal requirements.

You can get a mechanical permit as part of your construction permit, or you can get it separately.

You may also need a business license if your project is in Seattle, even if your office is outside the city.

How Much Does It Cost?

We base your permit fees on the value of construction plus an hourly review fee. We also collect an additional fire review fee for kitchen hood exhaust systems. All fees are subject to an additional technology fee. See our Fee Subtitle for details.

How Long Does It Take?

For most projects, you should plan for 9 weeks from the time you apply to the time we issue your permit. We try to finish our initial review of complex projects in 4 weeks, and 2 weeks for simple projects. We often ask you to make corrections after the initial review, which triggers a second review of your corrected plans.

The time it takes to get your mechanical permit depends on how complex your project is, how many corrections of your plans you need to make, how quickly and completely you respond, and how many projects are ahead of yours in the review queue.

If your project is simple, we can issue you a mechanical subject-to-field-inspection permit within 24 hours.  

Steps to Get Your Permit

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

Determine restrictions to your project. Research the codes to determine unit noise limits requirements.

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

Start your application. Complete the Building & Land Use Pre-Application online using the Seattle Services Portal. If you are applying for a mechanical STFI permit, you need to upload your plans and contractor information at the time of your application.

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. Request a pre-application site visit online through the Seattle Services Portal. One-hour pre-submittal conference fees vary based on the type of conference you need.

Get mechanical tech support. We offer technical backup support to answer questions before you apply for a mechanical permit. This service is available on a first-come, first-served basis for walk-in customers at the Applicant Services Center.

Apply for exemptions. You may need an exemption from code requirements if your project is located in an environmentally critical area or near the shoreline. You may also ask for a code modification if you propose to use a code that Seattle hasn’t yet adopted.

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

Fill out forms.

Coordinate with other agencies. You may need permits from other City of Seattle departments.

Prepare a complete set of drawings. Include a mechanical plan coversheet, vicinity map, site plan, and plans and elevations. For a detailed list of requirements see Tip 415, below. Also provide an equipment schedule (an example is in Tip 415) and heating and cooling load calculations where applicable. Be sure to list any exceptions you have taken.

  • Commercial Kitchen Hood Systems
    If you are installing a commercial kitchen hood, include the Commercial Kitchen Hood Worksheet as part of your drawing set on a full-size sheet.
  • Exterior Unit
    You need to show the dimensions from the unit to the property line on your plans. You must meet the standards in our noise code.
  • Units Weighing More Than 400 Pounds
    Include structural information when you submit your permit. You need to include calculations by a licensed structural engineer indicating the existing structure is adequate, as well as seismic calculations for unit anchorage. Include your unit seismic anchor details in your drawing set (full-size sheet), stamped by the structural engineer.

Schedule an intake appointment. You can schedule an electronic intake appointment once your screening is approved and you have completed all required preliminary application steps. You must upload all application documents by 7:00 a.m. on the day of your appointment. You do not need to be onsite during your intake appointment. However, you do need to be available for questions. We may call or email you on your appointment day for more information.

Tip: Submit your completed application early to be eligible for an earlier appointment in case of a cancellation. Once you submit your application, we'll add your project to the express lane. This means your application will likely be taken in well ahead of your scheduled appointment. We can usually take in your application within 2-3 weeks after you upload your complete application.

Pay fees. Approximately 75 percent of your permit fees are due at intake. The fees are calculated based on your project value. You must pay these fees before we will review your plans.

Make corrections and resubmit your plans. Your project reviewer will send you a corrections letter if changes are needed.

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.

Renew your permit. Your permit is valid for 18 months after the issue date. If your project is taking longer than that, you need to apply for a renewal.

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

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

Construction and Inspections

Nathan Torgelson, Director
Address: 700 5th Ave, Suite 2000, Seattle, WA, 98104
Mailing Address: P.O. Box 34019, Seattle, WA, 98124-4019
Phone: (206) 684-8600
Phone Alt: Violation Complaint Line: (206) 615-0808
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SDCI issues land use, construction, and trade permits, conducts construction and housing-related inspections, ensures compliance with our codes, and regulates rental rules. SDCI is committed to an antiracist workplace and to addressing racism through our work in the community.