Do I need a permit to replace my roof in Seattle?

Not for a like-for-like replacement — same pitch, same materials, same fastening pattern. If you're changing the framing, adding ventilation, increasing dead load, or upgrading to a wind-resistant system in a high-wind zone, you'll need a permit. Re-roofing is one of the few projects Seattle doesn't require a permit for, as long as the structure underneath stays the same. Verify with the city if your roof has any complexities (skylights, valleys, pitch changes).

How much does a permit cost in Seattle?

Permit fees are based on project valuation, typically 0.4 percent for residential work, capped at $6,500. A $10,000 deck costs roughly $40 (0.4 percent) but is often treated as a flat $75–$150 for over-the-counter permits. Electrical permits run $30–$80. Plan-check fees are bundled into the base permit cost. Inspection requests are free. If you need a structural engineer, geotechnical engineer, or energy audit, those are paid separately to the consultant, not to the city.

Can I pull a permit as the owner-builder?

Yes, on owner-occupied single-family homes. You must be the owner, the permit must be for your primary residence, and you cannot hire a general contractor. You can hire licensed specialty contractors (electricians, plumbers) — they'll pull their own subpermits. The building department may schedule more frequent inspections on owner-builder work, and you'll be responsible for correcting any deficiencies yourself. Many owner-builders report that inspections are thorough but fair.

How long does plan review take in Seattle?

Over-the-counter residential permits (decks, fences, simple remodels) are issued same-day or within 1–2 business days. Standard residential work averages 2–4 weeks. Complex projects (additions with seismic retrofit, geotechnical review, energy-code upgrade) can take 4–6 weeks. If the city finds issues, they'll flag them in an email and give you 2 weeks to resubmit. The eLink portal shows you your review status in real time.

What if my property is on a steep slope?

Seattle's steep-slope ordinance requires geotechnical review for any project on slopes steeper than 15 percent, or within 25 feet of a slope steeper than 25 percent. You can check the slope hazard zone on the city's interactive mapping tool (SDCI Maps). If you're in a hazard zone, you'll need a geotechnical engineer's report before you submit the building permit. That report costs $800–$2,500 and adds 2–3 weeks to the timeline. For decks and simple work, the report may be straightforward. For large excavations or retaining walls, it's more complex.

Do I need a permit for an attached greenhouse or sunroom?

Yes. An attached sunroom or greenhouse is a room addition and requires a permit. It needs proper egress (a door to the outside at grade level), foundation footings, insulation to the energy code (if it's heated), and electrical service if you want outlets or lighting. Most people are surprised that a greenhouse counts as living space for permit purposes. A detached greenhouse under 200 square feet might be exempt from a permit in some cases, but verify with the city first.

What's the deal with seismic tie-downs in Seattle?

Washington State updated seismic requirements in the 2022 IBC. Any new exterior wall, major framing repair, or lateral-bracing modification now requires cripple-wall bracing and foundation tie-downs if you're in a seismic zone (Seattle is Zone C). This means bolting your sill plate to the foundation and adding shear walls if needed. For most room additions, a structural engineer will specify this work; it's not optional. Older homes without tie-downs are grandfathered in, but any seismic retrofit work will trigger full compliance.

Can I file my permit online? How does eLink work?

Yes. eLink.Seattle.gov lets you submit most residential permits online with PDFs of your plans, site photos, and a completed application. You'll need to create an account (free) and upload documents. The system flags incomplete submittals immediately, so you know if a plan page is missing before you hit submit. Once filed, you can track your permit status, request inspections, and upload revised plans all online. Payment is by credit card at submission. Most people find eLink faster than walking into the building department counter.

What happens if I skip the permit?

Seattle's building department actively inspects properties, especially for visible work like decks, roof work, and additions. If an unpermitted project is discovered — often by a neighbor complaint or during title transfer — you'll be ordered to either bring it into compliance or remove it. Compliance costs more than the original permit would have: you'll owe a retroactive permit fee, back-inspection costs, and any corrections needed to meet code. You'll also lose the ability to claim the work for a home sale without full disclosure. For electrical work, unpermitted wiring is a serious issue — fire risk and insurance liability. The original permit cost ($75–$150) is always cheaper than the cleanup.

Building Permits in Seattle, WA (2026)

Do I need a permit in Seattle, WA?

Seattle enforces the 2022 International Building Code with Washington State amendments, which means most structural work, electrical, plumbing, and anything affecting egress or life safety requires a permit. The City of Seattle Building Department is strict about plan review — expect 2 to 4 weeks for standard residential work — but the city has invested heavily in digital permitting, so you can file online and track your application in real time. Seattle's wet climate and glacial-till soils come with their own quirks: frost depth is only 12 inches in the Puget Sound lowlands, but deck footings still need to be deeper than that if they're exposed to frost heave, and any work near a slope or in a steep-slope hazard zone will trigger additional geotechnical review. The city also sits in a seismic zone (USGS Zone C), so foundation work and any lateral-bracing changes will be scrutinized. Owner-builders are allowed on owner-occupied single-family homes, but only the owner — not a contractor — can pull the permit, and inspections are typically more rigorous. The good news: Seattle's permit fees are reasonable and capped based on project valuation, and the city processes residential projects faster than most West Coast jurisdictions.

What's specific to Seattle permits

Seattle's online permitting system is one of the most user-friendly in the country. You can file, upload plans, and track inspections at eLink.Seattle.gov. Most residential permits — decks, fences, basic remodels — can be submitted online with a PDF of your plans and a completed application. The system will flag incomplete submittals immediately, which saves weeks of back-and-forth. Over-the-counter permits (minor work with minimal plan review) are still processed at the Seattle Building Department counter, but filing online is faster for anything more substantial.

Seattle's adoption of the 2022 IBC with state amendments means seismic design is non-negotiable. Any foundation work, lateral bracing, or structural modification will require EQ (seismic) calculations if the building department flags it as seismic-sensitive. For most simple deck posts, this isn't an issue — but if you're adding shear walls, replacing a rim joist, or retrofitting lateral bracing, assume you'll need a licensed structural engineer's stamp. The cost of that stamp is typically $500–$1,500, depending on complexity.

Frost depth in Seattle proper is 12 inches — the shallowest in Washington State — but that doesn't mean you can shortcut footing depth. IRC R403.1.8 still requires footings to be below the frost line and, more importantly, below the active soil zone where frost heave can occur. On glacial-till soils (most of Seattle), that often means 18 inches below grade, even if frost doesn't penetrate that deep. The Building Department's detail sheets for deck construction spell this out; request them when you submit your permit.

Seattle's steep-slope requirements are strict. If you're building on a slope steeper than 15 percent, or within 25 feet of a slope steeper than 25 percent, the city triggers additional geotechnical review and may require a licensed geotechnical engineer's report. This adds 2–3 weeks and $800–$2,000 to a project. Before you break ground on a hillside home, verify the slope hazard zone on the city's interactive mapping tool.

The city is increasingly aggressive about green building and energy code compliance. Any remodel involving more than 25 percent of a home's exterior wall surface (by area) triggers the Washington State Energy Code, which requires upgraded insulation, air sealing, and sometimes HVAC work. Many homeowners are surprised to learn that re-roofing doesn't trigger energy-code upgrade, but replacing all windows, or a full wall replacement, does. The energy-code audit adds plan-review time but not usually additional permit cost.

Most common Seattle permit projects

These are the projects that Seattle homeowners submit most often. Click through to see local thresholds, typical fees, inspection timelines, and what plan details the Building Department will ask for.

Decks

Any attached or freestanding deck over 30 inches high requires a permit. Frost depth is 12 inches, but footings typically need to be 18 inches below grade on Seattle's glacial till. Deck permits are over-the-counter if no electrical or structural complexity; plan review is 1–2 weeks.

Fences

Fences over 6 feet, retaining walls over 4 feet, and any wall within a corner-lot sight triangle require a permit. Tall retaining walls on steep slopes trigger geotechnical review. Permit fee is typically $75–$150; add $500–$1,500 for slope analysis if required.

Roof replacement

Re-roofing doesn't require a permit in Seattle unless you're also replacing the roof framing. Siding replacement requires a permit only if you're changing the fire-rating of the exterior (e.g., wood to fiber-cement) or covering more than 25 percent of the wall in a seismic retrofit. Most homeowners are surprised by this; verify before you start.

Electrical work

New circuits, panel upgrades, outdoor outlets, and any hardwired appliance require an electrical permit. Seattle requires licensed electricians for permitted electrical work on owner-occupied homes. Permit fee is $30–$80 depending on work scope; inspections typically happen within 3 business days of request.

Room additions

Any addition, basement finish, or room remodel requires a permit and plan review. Seismic tie-downs are now required for new exterior walls. Plan review averages 3–4 weeks. Fees run 0.4 percent of project valuation, capped at $6,500 for residential work.

Windows

Individual window or door replacements don't require a permit. Replacing all windows in a room, or all windows on an exterior wall, triggers energy-code review. Entire-home window replacement (over 25 percent of exterior wall area) requires an energy audit and plan review.

Do I need a building permit in Seattle, WA?