Lewis County, Washington Building Permit Guide

Lewis County Community Development, 125 NW Chehalis Ave in Chehalis (360-740-1146), issues building permits for unincorporated Lewis County outside the Centralia, Morton, Pe Ell and Toledo urban growth areas (city-permitted since 2025), and inside Morton, Mossyrock and Pe Ell. A Master Site Review has to be approved before the building application goes in, and the county says a house permit generally takes two to four weeks to issue, longer in the May-to-October peak. Inspections are booked only in SmartGov.

What requires a building permit in Lewis County?

The county’s building handout, updated in September 2026, states the rule plainly: anyone who intends to construct, enlarge, alter, repair, move or demolish a building or structure, or change its occupancy, must obtain the permit, and it names decks as included. Separate mechanical and plumbing permits cover heating, gas and plumbing work, and placing a mobile home, park model, tiny home or factory-assembled structure has its own permit fee.

That list follows section 105.2 of the building and residential codes, with the smaller 120 sq ft limit for commercial accessory buildings. The handout itself still sends readers to the 2018 IBC and IRC for the complete list; the equivalent 2021 sections are the ones that apply now.

What the county decides and what the state holds

The handout records a local adoption of the 2021 International Codes on May 6, 2025, effective June 1, 2025; the 2021 state codes have applied statewide since March 15, 2024, and they are the codes in force. The same handout lists the county’s setbacks and heights: a house sits at least 25 feet from a county road right of way (and at least 55 feet from the road centerline), 5 feet from side lines and 15 feet from the rear, with a 35-foot height limit. Design wind speed is 85 mph, or 110 mph as a three-second gust. Commercial buildings keep 10 feet from side lines and may sit on the rear line except where they back onto a residential zone (25 feet), with a 50-foot height limit that drops to 35 feet within 50 feet of a residential zone. Wiring is not a county matter: Labor and Industries issues and inspects all electrical permits.

Lewis County building department: who handles permitting

Community Development combines a permit center, planning, building and fire safety, and code compliance. Doyle Sanford is the building official, fire marshal and floodplain manager. Environmental Health, in the same building, approves septic systems.

Which cities the county permits for

Three small cities send building permits to the county. For a project inside Morton, Mossyrock or Pe Ell, you first take the county’s City Approval Form, a city pre-application form and a site plan to the city, which certifies that the project meets its zoning and critical area rules and may charge its own fees; then you apply for the building permit at Lewis County Community Development. The other six cities run their own permits.

Urban growth areas

Under Resolution 25-300 the county signed co-management agreements in November 2025 with Centralia, Morton, Pe Ell and Toledo (a Vader agreement was authorized but is not yet posted). In each city’s unincorporated urban growth area the city now holds building permitting under its own code, while the county keeps septic and health, right-of-way, shoreline, frequently flooded areas and critical areas. You still file the Master Site Review or Land Development Review with the county first. The agreements run to June 30, 2035.

Permit types and what comes first

Residential permits

One complete set of legible plans is enough: a foundation plan with sizes, materials and reinforcement; a floor plan for each floor showing plumbing fixtures, heating, doors, windows, room uses and square footage; wall cross sections; elevations of every side; and a roof plan. An addition also needs the existing layout. A house or accessory building with an eave height of 14 feet or more must be designed and stamped by a licensed structural engineer, and the building official can require engineering on other projects. A well needs a well report showing its yield in gallons per minute.

Building or remodeling a home here? Alliance handles residential permit applications, so the crew isn't waiting on the counter.

Commercial permits

Every commercial project needs plans by a Washington-licensed architect or engineer. Commercial, industrial and multi-family permits take at least four weeks, and the 2026 schedule charges plan review at 65 percent of the permit fee, or 40 percent for agricultural buildings over 10,000 sq ft and for utility pole buildings with a clear span of 40 feet or more.

For tenant improvements and new commercial builds, Alliance handles commercial building permits through issuance. More on this: commercial building permits explained.

What comes before the building permit

• Master Site Review: required and approved before any building permit can be submitted; it checks the proposal against zoning and the critical areas ordinance ($440, or $110 for a minor review).
• Floodplain: all development in the floodplain needs a floodplain development permit ($90) under Lewis County Code chapter 15.35. Improvements or repairs worth more than 50 percent of a building’s value, tracked cumulatively over ten years, must meet new-building flood standards.
• Septic: Environmental Health issues the septic permit; the system must be final-approved before the house final.
• Road approach and water: the road approach must be permitted and finaled, a well needs a well report, and the house final also needs a satisfactory bacteria test from the last year and a nitrate test.
• Shorelines: a shoreline exemption review is $220 and a substantial development permit $3,125.
• Fill and grade: up to 50 cubic yards needs no grading fee; 51 to 100 cubic yards is $19.69 plan review plus a $29.54 permit, and from 101 to 1,000 cubic yards the permit is $29.54 plus $13.79 for each further 100 yards. A driveway that needs fill can need this permit even though driveways are exempt from the building permit.

Lewis County building permit fees

The county’s 2026 fee schedule (Exhibit A to Resolution 25-312, adopted November 4, 2025, effective January 1, 2026) prices the building permit from the county’s standardized building valuation and Table 1, and adds a $50 administrative fee and a $10 technology fee to every application. In its own words, the Table 1 “fees do not include State Fee or related permit fees such as mechanical, plumbing, etc.”

Worked example: a $300,000 house falls in the $100,001 to $500,000 band, so the Table 1 fee is $1,304.34 plus 200 × $7.35 = $2,774.34. Plan review is 65 percent of that base fee, and the $50 administrative fee, $10 technology fee, Master Site Review, state fee and any mechanical and plumbing permits are added. If you withdraw before any review, up to 80 percent of the permit fees can be refunded; once plans are approved, plan review fees are not refunded.

Trade permits and who may pull them

Community Development issues mechanical and plumbing permits, either with the building permit or as stand-alone permits priced per fixture or element with a $100 inspection fee; element fees on the 2026 schedule include $14.80 for a furnace or heat pump under 100,000 Btu, $10.65 for a fireplace insert and $5.50 for gas piping with one to four connections. Electrical permits and inspections come only from Labor and Industries. As for who may do the work: paid builders register with L&I, electricians and plumbers carry L&I licenses, and owners have a limited right to work on their own homes under state law (Washington contractor licensing).

• Septic installers and designers: Lewis County posts its own 2026 applications for septic installers, pumpers and designers.

How to apply for a Lewis County building permit

Review, corrections and what causes delay

A house permit generally issues two to four weeks after the plans go in, and commercial, industrial and multi-family permits take at least four, but the county warns that every permit takes longer in the May-to-October building season, so apply early. Plans that do not meet the submittal list can draw extra fees, and changes after approval cost $50 plus hourly review. A permit is valid for 180 days after issuance and stays valid for 180 days after each inspection; the building official may extend it if you ask before it expires.

Inspections

Building inspections are requested only through SmartGov. A request in by 6:30 a.m. can be inspected that day; later requests move to the next day. The list of addresses being inspected is posted each day by 9:30 a.m. Re-inspection is $100 when corrections were not made, the work was not ready, the site was locked, or the approved plans and permit were not on site.

Before the final inspection on a new house, the septic system must be final-approved (with the as-built or installer’s checklist), the road approach finaled, and the bacteria and nitrate water test results submitted, along with any other condition on the permit. The L&I electrical final is separate. Elevation certificates for floodplain homes are kept on file and many can be viewed on the county GIS web map under “Zoning & Permitting”.

Washington building code and flood maps

Lewis County enforces the 2021 Washington codes, with floodplain rules in Lewis County Code chapter 15.35. FEMA’s Community Status Book lists Lewis County as a participating National Flood Insurance Program community with a Community Rating System class of 5, along with Centralia, Chehalis, Morton, Napavine, Pe Ell, Toledo, Vader and Winlock; Mossyrock is not listed in the book.

Washington has a mandatory statewide building code under chapter 19.27 RCW that every city and county enforces and may make stricter; electrical permits come from the Department of Labor and Industries unless the city runs its own program or Tacoma Power serves the site. Building codes in Washington

Lewis County building permit FAQ

Does Lewis County issue permits inside any cities?

Yes: in Morton, Mossyrock and Pe Ell, after the city signs the City Approval Form. Centralia, Chehalis, Napavine, Toledo, Vader and Winlock issue their own. In the urban growth areas of Centralia, Morton, Pe Ell and Toledo, the city issues the building permit after the county approves the site review.

How long does a house permit take?

Generally two to four weeks after submittal, and longer from May through October.

How much is a permit for a $300,000 house?

$2,774.34 on Table 1, plus 65 percent plan review, the $50 administrative and $10 technology fees, and the Master Site Review.

Can I build a shed without a permit?

Yes, a one-story detached shed of 200 sq ft or less at a home with no habitable space; zoning setbacks still apply.

What is the cut-off for a same-day inspection?

6:30 a.m., requested in SmartGov.

Do I need a permit to build in the floodplain?

Yes. All floodplain development needs a $90 floodplain development permit; call Community Development on 360-740-2696 first.

Permit search and official resources

Current permits and inspections are in SmartGov. Older Community Development files are in the county’s online records search, and anything not posted can be requested through the county’s public records office.

• Lewis County Community Development
• Lewis County SmartGov portal
• Building permit handout (September 2026)
• 2026 fee schedule (Exhibit A, Resolution 25-312)
• City Approval Form for Morton, Mossyrock and Pe Ell
• Permit applications and handouts
• Building inspections
• Floodplain construction rules
• Codes and flood regulations
• Septic permit application
• Lewis County Environmental Health
• L&I city electrical programs
• L&I contractor registration
• FEMA Community Status Book, Washington

Simplify Lewis County permitting with Alliance Permitting

Alliance Permitting is a permit documentation and submission company in Washington. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Lewis County permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.