City of Seattle building permits: fees, timelines & requirements (2026)
What needs a permit in City of Seattle and what triggers one — each row quoted from the city's own code or permit page, with the source linked and the source page checked daily for changes. Fees and review times appear where the city publishes them. Covers ADU, addition, kitchen, bathroom, basement, deck, fence, siding, windows, flooring, roofing, HVAC, electrical, plumbing, and ancillary permits (King County).
21 of 24 project types have authoritative rules on file · 13 always require a permit · 10 depend on the scope · 0 do not.
Get your lot in 3D with zoning, setbacks, and the exact permits your project needs — cited to City of Seattle's source.
Permit department
Seattle Department of Construction & Inspections (SDCI)
Adopted code cycles
2021 IRC w/ WA amendments · 2021 WSEC
Resources
Construction permits
| Project | Permit? | Threshold | Fee | Review days | Source |
|---|---|---|---|---|---|
| Kitchen remodel | Depends on scope | No permit for cabinets, counters, paint or tile. A permit once you move plumbing, add circuits, run gas or change walls. Cosmetic-only refresh exempt. Most full kitchen remodels touch electrical (new circuits for dishwasher/disposal/microwave) and plumbing (sink/dishwasher), so plan on Construction Permit (Subject-to-Field-Inspection if no structural change) plus electrical, plumbing, mechanical permits. | Subject-to-Field-Inspection if no structural change. See 2026 SDCI Fee Subtitle. | Not published by the city | Cite verified 2026-04-26 |
| Bathroom remodel | Depends on scope | No permit for tile, paint or a same-spot fixture swap. A permit once plumbing moves, circuits are added or the tub or shower goes. Like-for-like fixture replacement in same location with no plumbing rerouting and no new circuits is sometimes exempt; any relocation, new fixture, or circuit change triggers permits. | Subject-to-Field-Inspection typical. Plus electrical, plumbing, mechanical permits. | Not published by the city | Cite verified 2026-04-26 |
| Basement finish | Always | Finishing a basement into habitable space needs a building permit; egress and ceiling height are the usual review items. Adding habitable rooms requires Construction Permit. Egress window required for any sleeping room (2021 IRC R310). Ceiling-height minimums and emergency-escape openings are common rejection reasons. | Construction Permit (Addition/Alteration). Plan-review fee scales with valuation. See SDCI 2026 Fee Estimator. | Not published by the city | Cite verified 2026-04-26 |
| Deck | Depends on scope | A deck 18 in or less above grade, not a roof deck and outside an ECA is exempt. Above 18 in, a roof deck, or any deck in an ECA needs a permit. Permit required if: deck >18in above grade, OR roof deck, OR in an ECA. Decks ≤18in above grade and outside ECAs are exempt. If deck >36in above grade, it counts toward lot coverage. If deck >8ft tall, has long beams, is a roof deck, or in an ECA → Construction Permit (Addition/Alteration); otherwise Subject-to-Field-Inspection. | Subject-to-Field-Inspection permits pay 40% of plan-review fee from SDCI Fee Estimator. See 2026 Fee Subtitle. | Not published by the city | Cite verified 2026-09-24 |
| Fence | Depends on scope | No permit for a fence 8 ft or under with no masonry over 6 ft, outside a flood zone and not in or near an ECA. Any one of those needs a permit. No permit required if ALL of: ≤8ft tall, no masonry/concrete >6ft, not in a flood zone, not in/near an ECA. NR zones: 6ft standard, up to +2ft architectural features. Sloping sites: max 8ft if avg height between posts is 6ft. | Construction Subject-to-Field-Inspection permit when required. See 2026 SDCI Fee Subtitle. | Not published by the city | Cite verified 2026-09-24 |
| Siding | Depends on scope | Replacing siding needs no building permit in Seattle. Changing structure, replacing sheathing, or altering doors or windows needs one. Seattle Residential Code R105.2 item 10 exempts siding replacement from a building permit: "Replacement of siding. This shall not include structural changes, replacement of sheathing or alteration to doors and windows." A permit is needed when the job changes structure, replaces sheathing, or alters doors or windows. Item 10 refers insulation to Energy Code R503.1.1, Exceptions 2 and 3. | Often exempt. If permit required, Subject-to-Field-Inspection. | Not published by the city | Cite verified 2026-09-24 |
| Window replacement | Depends on scope | Same-size replacement in the existing opening is exempt. A new or enlarged opening, an egress change or a header change needs a Subject-to-Field-Inspection permit. Like-for-like replacement in existing rough opening with U-factor compliance: typically exempt. New opening, enlarged opening, change in egress compliance, or any structural header change requires Subject-to-Field-Inspection permit. | Like-for-like usually no permit. Structural changes scale with valuation. | Not published by the city | Cite verified 2026-04-26 |
| Flooring | Depends on scope | Surface flooring is exempt. Subfloor or joist work, or radiant heat, needs a permit. Surface flooring exempt under 2021 IRC R105.2. Subfloor structural modification, joist alterations, or radiant heat install requires permit (mechanical/electrical for radiant). | No permit fee for surface flooring. | Not published by the city | Cite verified 2026-04-26 |
| ADU / DADU | Always | An ADU or DADU always needs a building permit, and usually trade permits with it. Max 2 ADUs per property. Pre-approved DADU plans via ADUniverse cut review to 2-6 weeks; custom designs follow standard plan submittal (SDCI Tips 103 + 106). OWNER-OCCUPANCY IS NOT REQUIRED and cannot be — RCW 36.70A.681(1)(b) bars a city from requiring the owner to occupy the ADU or another unit on the lot, so both units may be rented. A covenant recorded under the old rule can be released; SDCI publishes the Release of Owner Occupancy Covenant for ADUs form for exactly that. | Construction Permit (Addition/Alteration). Pay 75% of plan-review + permit fees at application acceptance. See 2026 Fee Estimator + Director's Rule 5-2025. Pre-approved DADU plans waive most plan-review fees. | Not published by the city | Cite verified 2026-09-24 |
| Roofing | Depends on scope | A roof recover or a like-for-like roof replacement needs no building permit in Seattle. Replacing sheathing, changing the framing or pitch, or adding skylights or other changes to the building envelope needs one. Seattle Residential Code R105.2 lists as work exempt from a building permit: "11. Roof recover." and "12. Roof replacement if no changes are made to the building envelope other than adding or replacing insulation, and the work is equivalent to or better than the existing structure. Permits are required for structural changes and replacement of sheathing of any size." Energy Code R503.1.1, Exceptions 2 and 3, still set the insulation requirement where the roof cavity is exposed. | Re-Roof Permit — flat fee. See 2026 SDCI Fee Subtitle. | Not published by the city | Cite verified 2026-09-24 |
| HVAC | Always | Any equipment install or replacement needs an SDCI mechanical permit. SDCI requires Mechanical Permit for any equipment install or replacement. WSEC R403 requires Manual J/S/D sizing on new systems. | Mechanical permit + electrical (if new circuit) + plumbing (if condensate to drain). | Not published by the city | Cite verified 2026-04-26 |
| Electrical | Always | Every piece of residential electrical work needs an electrical permit from SDCI, which issues and inspects inside city limits. Electrical permit required for ALL electrical work in residential. Seattle runs its own electrical program: SDCI issues AND inspects electrical permits inside city limits (NOT L&I — L&I only handles contractor licensing). Most residential work is issued over the counter, same day, online through the Seattle Services Portal; OTC eligible under 5,000 sf or under 400 A. Plan review only per Seattle Electrical Code Art. 80 §80.50/80.51. | SDCI electrical permit fees by circuit count + service size, per the Seattle fee schedule. Not an L&I fee — L&I only collects the contractor licensing fee. | Not published by the city | Cite verified 2026-07-27 |
| Plumbing | Depends on scope | A like-for-like fixture or faucet in the same location is generally exempt. Installing, replacing or relocating anything else needs a plumbing permit — from Public Health, not SDCI. SDCI does NOT issue plumbing permits in Seattle — the Seattle Plumbing Code is enforced by Public Health – Seattle & King County, and plumbing permits are applied for there. Side sewer is a third authority (SPU). WAC 51-56 requires a plumbing permit for installation, replacement, or relocation; like-for-like fixture/faucet replacement in the same location is generally exempt. Separately, SDCI requires no construction permit for minor repairs or alterations costing $6,000 or less in any 6-month period — but that exemption never covers load-bearing supports, building-envelope changes, or work reducing egress, light, ventilation or fire resistance, regardless of cost. | Plumbing permit fees are set by fixture count in the city's fee schedule. | Not published by the city | Cite verified 2026-07-27 |
| Addition | Always | Adding floor area always needs a building permit. Any additional floor area requires Construction Permit (Addition or Alteration). Plan review required. ECA + lot coverage + setback compliance verified at intake. | Construction Permit (Addition/Alteration). Pay 75% of plan-review + permit fees at application acceptance. See SDCI 2026 Fee Estimator. | Not published by the city | Cite verified 2026-04-26 |
Ancillary & non-building permits
| Project | Permit? | Threshold | Fee | Review days | Source |
|---|---|---|---|---|---|
| Demolition | Always | Demolishing a structure or a substantial part of one needs a permit; asbestos and lead notifications are separate. 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. | Demolition fees commonly charged as flat fee or by structure size. State surcharge $6.50 applies. | Not published by the city | Cite verified 2026-05-02 |
| Right-of-way | Always | Any work in or occupation of the public right of way needs a right-of-way permit from public works. Issued by city public works (or SDOT in Seattle) under local ROW ordinance. Triggered by physical occupation of or work within the public ROW including driveway aprons, curb cuts, sidewalk replacement, utility tie-ins, hauling routes, and temporary construction staging. | Right-of-way permit fees vary by city: a base fee for a residential driveway or curb cut, plus a per-day occupancy charge if the street is obstructed. | Not published by the city | Cite verified 2026-05-02 |
| Side sewer | Always | A new side-sewer connection, a repair beyond about 2 ft, relining or capping needs a permit from whichever utility owns the main. The side-sewer permit is issued by whichever utility owns the sanitary sewer — the city, a sewer or water district, or a regional utility — under that utility's own code, with WAC 51-56 (2021 UPC) governing how the building sewer is laid. WHICH UTILITY IS A PER-PROPERTY FACT: a lot can sit inside a city for permitting and outside its sewer district, so confirm the owner of the main before applying. Triggered by a new connection, repair of more than about 2 ft of pipe, relining (CIPP), or capping at the property line for a demolition. | Side-sewer permit fees are set by the utility that owns the main; some add a depth-based surcharge. Utility-issued, not building-permit-issued. | Not published by the city | Cite verified 2026-09-06 |
| Stormwater / drainage | Always | New or replaced impervious surface and land disturbance are reviewed under the drainage manual this jurisdiction adopts; the threshold is the manual's. Ecology's Stormwater Management Manual for Western Washington (SWMMWW, 2024 edition) is the state floor. A municipal stormwater permittee may instead adopt a REGIONAL manual Ecology has determined equivalent, and most do — some counties publish their own, some cities publish their own, and others adopt Ecology's directly. WHICH MANUAL APPLIES IS A PER-JURISDICTION FACT and it changes the numbers: review thresholds for new plus replaced impervious surface and for land-disturbing activity differ between manuals, so read this jurisdiction's own adopting chapter before quoting one. Critical-area and closed-basin parcels get stricter review under every manual. | Drainage review fees are commonly tiered by project size in the city's fee schedule. | Not published by the city | Cite verified 2026-09-06 |
| Land-use / zoning | Always | A variance, conditional use, plat or design review is a land-use decision that precedes the building permit. Triggered when a project does not conform to the strict letter of the zoning code. Variances require a hardship finding under most city codes. Design review thresholds vary (Seattle: most multifamily + non-residential >4,000 sqft; many cities: design review only in designated districts). | Land-use fees vary widely; a variance usually carries an application fee plus cost recovery for the hearing examiner. | Not published by the city | Cite verified 2026-09-24 |
| Tree removal | Depends on scope | Trees under 6 in are not regulated. Up to two trees of 6 to under 12 in may be removed in any three years. Larger trees, grove trees and listed species may not be removed unless SDCI approves them as hazardous, or in an emergency. When no development is proposed (SMC 25.11.050): trees under 6 in DSH are not regulated. On a developed lot in a Neighborhood Residential, Lowrise, Midrise, commercial or Seattle Mixed zone, no more than two Tier 4 trees may be removed in any three-year period (Tier 4: 6 in to under 12 in DSH). Tier 3 (12 in to under 24 in), Tier 2 (24 in or more, every tree in a grove, and species named by Director's Rule) and Tier 1 (heritage) trees may not be removed unless deemed hazardous or in need of emergency action, with documentation. Hazardous removal needs SDCI approval in advance, on a tree risk assessment by a registered tree service provider rating the tree Extreme or High risk (SMC 25.11.040). The Director may also allow removal of a Tier 3 or Tier 4 tree that is damaging a foundation or utilities (SMC 25.11.050.D). On an undeveloped lot, Tier 1 to 4 trees are all protected. | Seattle issues no tree-removal permit when no development is proposed. A hazardous-tree removal is approved by SDCI on a registered tree service provider's risk assessment (SMC 25.11.040); Kolmo has not verified what SDCI charges for that review. | Not published by the city | Cite verified 2026-09-21 |
| Signs | Always | Permanent signs need a sign permit; small temporary residential signs are usually exempt. City sign code (typically Title 22 or 23) governs. Wall, freestanding, projecting, awning, and electronic message signs all require permits. Most cities exempt small temporary residential signs (real-estate, political) under area thresholds (~6 sqft). | Sign permit fees are set in the city's fee schedule, plus an electrical sub-permit for an illuminated sign. | Not published by the city | Cite verified 2026-09-06 |
Building in City of Seattle?
Kolmo Construction is a licensed Washington general contractor — KOLMOL*753JS, bonded and insured — working throughout City of Seattle and King County. We pull the permits listed above and build the project.
How this page is built
Each row is the most-recently-verified authoritative rule on file for City of Seattle and the listed project type. “Pending verification” means we have City of Seattle in our database but haven't yet personally checked the city page for that project — those rows fall back to King-County or Washington-state baselines until verified.
See the data-quality leaderboard for how we keep these current, or run an address-specific lookup on the main permits page.