Yes, that replacement needs a permit. Here's who issues it.
Washington requires mechanical permits for virtually every furnace and heat pump replacement — the rules just differ by city. We pull the permit on every job; here's the map.
Quick answer
Every jurisdiction we serve requires a mechanical permit for replacing a furnace, heat pump, or AC — like-for-like included. Fuel-switch projects (gas → electric heat pump) add an electrical permit, often through WA Labor & Industries. As your licensed contractor (WA Lic. INFINHA841B8), Infinity files all of it — permits and inspections are part of the job, not your homework.
Unincorporated Pierce County (Graham, Spanaway, Frederickson)
Pierce County Planning & Public Works
Like-for-like replacement: Yes — a mechanical permit is required even for same-spot furnace or heat pump replacement.
Basic replacement permits are typically issued right after fee payment. Homeowners may pull their own permit on a primary residence; we pull it as your licensed contractor so nothing gets missed.
Official portal: Pierce County residential permitsCity of Tacoma
Tacoma Planning & Development Services
Like-for-like replacement: Yes — mechanical permit (MECHR). An expedited ePermit exists ONLY for direct replacements with no new venting/ductwork and no BTU increase.
Tacoma prohibits converting electric heat to gas via the expedited path — the city's rules lean electric, which suits heat pump conversions well.
Official portal: tacomapermits.orgCity of Federal Way
Federal Way Building Division
Like-for-like replacement: Yes — permit required; simple replacements can go Over-The-Counter.
Federal Way requires the exact weight of old vs new equipment on submittals; heavier units (or ≥400 lbs) trigger engineered structural calcs. We prepare that paperwork.
Official portal: MyBuildingPermit.comCity of Kent
Kent Permit Center
Like-for-like replacement: Yes — filed as a residential mechanical 'Minor Work Permit'.
Kent doesn't issue residential electrical permits — HVAC electrical work is permitted separately through WA Labor & Industries. We coordinate both.
Official portal: MyBuildingPermit.comCity of Auburn
Auburn Community Development, Building Services
Like-for-like replacement: Yes — mechanical permit required for primary equipment replacement.
Like Kent, Auburn defers electrical permitting to WA L&I — fuel-switch projects need both permits coordinated.
Official portal: MyBuildingPermit.comCity of Puyallup
We verify current processCity of Puyallup (verify current process)
Like-for-like replacement: Washington code requires mechanical permits for equipment replacement statewide; Puyallup's specific process details weren't verifiable in our July 2026 review.
We confirm the current Puyallup submittal path when we schedule your install — permits are on us either way.
Official portal: cityofpuyallup.orgCity of Lakewood
We verify current processLakewood Building Department (verify current portal)
Like-for-like replacement: A mechanical permit is required under statewide code; Lakewood's own portal details weren't verifiable in our July 2026 review.
We verify the current Lakewood process at scheduling time and handle the filing.
Official portal: cityoflakewood.usWe handle the permit paperwork. All of it.
Mechanical permit, L&I electrical coordination on fuel switches, equipment-weight submittals where cities require them, and the inspection. It's included on every Infinity install across the South Sound.
Permit questions
Do I really need a permit just to replace my furnace with the same kind?
In Washington, almost always yes. Replacing a primary heating appliance — even like-for-like in the same spot — requires a mechanical permit in every jurisdiction we work. The exemptions are narrow: minor internal parts, portable plug-in units, and small self-contained systems. Unpermitted swaps surface at home sale time and can void insurance arguments.
Can I pull my own permit as the homeowner?
Washington lets owner-occupants pull permits on their primary residence. In practice, when a licensed contractor does the work, the contractor pulls it — that's part of what you're paying for, and it puts the inspection responsibility on us, not you.
Why do heat pump conversions sometimes need TWO permits?
Switching fuel (gas furnace to electric heat pump) triggers a mechanical permit AND an electrical permit. In cities like Kent and Auburn, the electrical side is permitted through WA Labor & Industries rather than the city. We coordinate both so the project never stalls on paperwork.
Does the permit slow the job down?
Rarely, if it's filed right. Simple replacement permits in Pierce County typically issue right after fee payment, Tacoma has an expedited ePermit for direct swaps, and the MyBuildingPermit.com cities process minor mechanical work in a few business days. We build the paperwork before install day.
Continue exploring
Verified July 2026 · Official portals linked per jurisdiction · Processes change — we confirm at scheduling
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