HVAC permits in Seattle: fees, timeline & requirements (2026)
Everything you need to know about pulling an HVAC / mechanical permit in Seattle, Washington — when one is required, what it costs, how long review takes, what documents are required, and which inspections you can expect. Cited to Seattle Department of Construction & Inspections (SDCI).
Free lookup, no account needed — the office that issues the permit at your address, the mapped areas on the lot, cited to Seattle's source.
When does HVAC work need a permit in Seattle?
SDCI requires Mechanical Permit for any equipment install or replacement. WSEC R403 requires Manual J/S/D sizing on new systems.
How Seattle adopted this rule
The threshold comes from the state code (WAC 51.52), which Seattle adopts by reference in the provision quoted below.
“Table A for 22.101.010 lists various adopted Seattle editions of construction codes. For each base code that has been adopted by reference, a copy is available in the City Clerk's Office under the listed Clerk File number. Each code consists of the listed portions of the base code, any additional chapters listed as adopted by ordinance, and amendments adopted by ordinance.”Source ↗verified 2026-04-26
Required submittals
- Equipment specs
- Manual J/S/D for new system
- Gas piping diagram if applicable
- Electrical permit cross-reference
Inspection sequence
- Rough-in / gas pressure test
- Final
Contractor specialties needed
HVAC contractor · Electrician (journey-level 01 or residential 02)
Who can do this work in Seattle?
Kolmo Construction is a licensed Washington general contractor — KOLMOL*753JS, active through April 10, 2027, bonded and insured — working throughout Seattle and King County. Kolmo manages the HVAC / mechanical job from start to finish: a licensed HVAC subcontractor performs the work and the permit, and Kolmo coordinates the scope, schedule, inspections and any related construction. Call (206) 410-5100 for a Seattle HVAC / mechanical quote.
Notes & caveats
Heat pump: electrical permit for new circuit. Gas line: leak test required. WA HEEHRA rebates available for heat pumps (energy.wa.gov).
How to apply yourself
- 1. Check who issues the permit. Run an address lookup for your HVAC work in Seattle — we'll confirm which office issues the permit at that address and whether the lot is in a critical area or a flood hazard area, which Seattle's rule turns on.
- 2. Assemble submittals: the 4 documents under Required submittals above.
- 3. Submit through the city portal: Seattle Department of Construction & Inspections (SDCI) ↗
- 4. Track review. Respond to reviewer comments promptly.
- 5. Pay issuance fees (Seattle's fee schedule sets them) and pick up the permit. Inspection card travels with the job.
Or have Kolmo do it
Kolmo runs the job: a licensed HVAC subcontractor does the HVAC / mechanical work and pulls the permit, and Kolmo coordinates the scope, schedule, inspections and any related construction.
Licensed WA general contractor KOLMOL*753JS · bonded & insured
HVAC permits in Seattle — FAQ
When does HVAC work need a permit in Seattle?
SDCI requires Mechanical Permit for any equipment install or replacement. WSEC R403 requires Manual J/S/D sizing on new systems.
How much does an HVAC / mechanical permit cost in Seattle?
Where HVAC work needs a permit, SDCI's mechanical permit fee is $60.35 for each furnace, heat pump or wall heater and $59.85 for each appliance vent installed separately. A ducted air-moving system on its own permit is priced on the Development Fee Index with a one-hour plan review minimum at $292 an hour; when its plans are reviewed with the building permit, the mechanical permit is part of it at no added fee. A new circuit takes an SDCI electrical permit ($43.80 for 30 to 50 amps, plus the $55.48 administrative fee), and gas piping a Public Health – Seattle & King County permit. A 5% technology fee is added to SDCI fees (SMC 22.900D.090).