Demolition permits in Mercer Island: fees, timeline & requirements (2026)
Everything you need to know about pulling a demolition permit in Mercer Island, Washington — when one is required, what it costs, how long review takes, what documents are required, and which inspections you can expect. Cited to Mercer Island Community Planning & Development.
Free lookup, no account needed — your lot polygon, zoning, setbacks and overlays, cited to Mercer Island's source.
When does a demolition need a permit in Mercer Island?
2021 IBC Section 105.1 + WA-adopted IRC R105.1: demolition of any structure or portion thereof requires a permit. Tear-out of interior finishes only is generally treated as alteration. Asbestos / lead notification often required separately under WAC 173-303 / 296-62.
How Mercer Island adopted this rule
The threshold comes from the state code (WAC 51.51), which Mercer Island adopts by reference in the provision quoted below.
“The 2021 Edition of the International Residential Code (IRC), as adopted and amended by the State Building Code Council in WAC Chapter 51-51”Source ↗verified 2026-10-02
Required submittals
- Site plan
- Utility disconnect confirmations
- Asbestos survey (pre-1981 structures)
- Erosion / sediment control plan
- Haul route if structure >1500 sqft
Inspection sequence
- Pre-demo (utilities + erosion)
- Mid-demo if multi-day
- Final site stabilization
Contractor specialties needed
General contractor
Who can do this work in Mercer Island?
Kolmo Construction is a licensed Washington general contractor — KOLMOL*753JS, active through April 10, 2027, bonded and insured — working throughout Mercer Island and King County. Kolmo prepares the drawings and submittals, files the demolition permit with Mercer Island Community Planning & Development, carries the project through review and inspections, and performs the construction. Call (206) 410-5100 for a Mercer Island demolition quote.
Notes & caveats
Disconnect notices required from utilities (gas, electric, water, sewer) before issuance. Erosion control plan required where soil is disturbed. Bonded contractor typically required. Site stabilization + capped sewer line at completion.
How to apply yourself
- 1. Confirm your parcel's zoning & overlays. Run an address lookup for your Mercer Island demolition — we'll pull your specific lot polygon, zoning, setbacks, and any shoreline/ECA/historic overlays.
- 2. Assemble submittals: the 5 documents under Required submittals above.
- 3. Submit through the city portal: Mercer Island Community Planning & Development ↗
- 4. Track review. Respond to reviewer comments promptly.
- 5. Pay issuance fees (Mercer Island's fee schedule sets them) and pick up the permit. Inspection card travels with the job.
Or have Kolmo do it
Kolmo prepares the drawings and submittals, files with Mercer Island Community Planning & Development, handles reviewer comments, and builds the project.
Licensed WA general contractor KOLMOL*753JS · bonded & insured
Demolition permits in Mercer Island — FAQ
When does a demolition need a permit in Mercer Island?
2021 IBC Section 105.1 + WA-adopted IRC R105.1: demolition of any structure or portion thereof requires a permit. Tear-out of interior finishes only is generally treated as alteration. Asbestos / lead notification often required separately under WAC 173-303 / 296-62.
How much does a demolition permit cost in Mercer Island?
Mercer Island's demolition permit is $430 for a single-family house and $214 for a soft or partial demolition; further plan review and inspection is $182 an hour (2026 Fee Schedule).