Sammamish, Washington Building Permit Guide

Sammamish sits on a plateau between Lake Sammamish and the Snoqualmie Valley, and its development code treats the tree canopy as a quantified resource rather than an aesthetic one. The numbers are written into the code by zone, which makes them plannable but also unavoidable.

Community Development handles building and land use permitting, with a published applications and forms library covering applications, environmental review, forms and checklists, and guides. Critical areas studies attach where critical areas or buffers are present.

This guide covers work inside the Sammamish city limits. Unincorporated King County is permitted by the county, and the neighbouring eastside cities administer the state code themselves.

What requires a building permit in Sammamish?

Washington has a mandatory statewide building code. The codes enumerated in chapter 19.27 RCW, the State Building Code Act, are adopted and amended by the State Building Code Council within the Department of Enterprise Services, and they are required in all cities and counties — local government administers and enforces them rather than deciding whether to have them. A city or county may make the state code stricter but cannot opt out of it, and local changes affecting houses or apartments need State Building Code Council approval. So the question in Sammamish is not whether a code applies, but which edition is in force and what Sammamish Community Development has added to it.

Local amendments, fee schedules and exempt thresholds differ from one jurisdiction to the next, so an exempt list from a neighbouring city is not reliable. An exemption from a building permit is never an exemption from zoning, critical areas review, the energy code or a trade permit. Confirm scope with Sammamish Community Development before work starts.

Local rules worth knowing

There is an incentive worth designing for: permanently preserving a landmark tree earns retention credit at 200 per cent in some circumstances and 150 per cent in others, so a single well-placed preservation can satisfy a materially larger share of the requirement than its own count suggests

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 programme or Tacoma Power serves the site. Building codes in Washington

Who handles permitting in Sammamish?

Community Development issues building, land use and site development permits, with the director holding significant discretion over studies, mitigation and construction timing where critical areas are involved. All applications are submitted online through MyBuildingPermit.com; the Permit Center answers questions but does not issue permits at the counter.

The wet season carries real authority here. Construction associated with subdivisions and similar projects draining to the lake during the wet season must provide water quality monitoring reports to the city, and the director may halt wet season construction as necessary to protect the hazard area or to prevent downstream impacts. On sites with erosion hazard areas, existing vegetation must be retained on lots until building permits are approved for development.

Retention exemptions are narrow and specific: significant trees determined to present an imminent danger, and significant trees located in public utility easements and public rights of way, are exempt from the retention calculation. Where protected areas are required, their location, purpose and restrictions must be shown on the face of the deed, plat or covenant and recorded, and cannot be modified without the city’s written approval.

In 2025, building permits issued in Sammamish authorized 45 new privately owned housing units, all of them single-family homes, according to the U.S. Census Bureau Building Permits Survey.

Permit types

Residential permits

Single family residence applications carry a published submittal checklist, and where the applicant is unsure whether critical areas or buffers are present the city recommends contracting a qualified professional to review on-site and surrounding conditions. A critical areas study must be submitted as part of the application where they are present.

How Washington contractor credentials work

Commercial permits

Site development permit plan sets must be stamped, signed and dated by a civil engineer licensed in Washington, must label and delineate all critical areas, buffers and critical area building setbacks, and must show existing significant trees on site, along the frontage and any tree whose drip line falls within the site.

Registrations, trade certifications and design professionals

Three credential layers appear on Washington projects: the state contractor registration under chapter 18.27 RCW, which nearly everyone doing the work needs; separate state trade certification for electricians and plumbers, each examined and administered by its own programme; and, on commercial and larger residential work, drawings stamped by a Washington-licensed architect or professional engineer. Confirm what Sammamish Community Development requires for the specific building before filing.

Most Washington contractors register with the Department of Labor and Industries (with a surety bond and insurance) rather than holding a licence; electrical and plumbing contractors also need an L&I contractor licence. Contractor licensing in Washington

Sammamish permit costs and fees

Sammamish publishes fees alongside its applications, with each application listing required documents and fees. Critical areas studies, arborist reports and civil engineering are project costs on top of the permit fee and often exceed it on constrained sites.

Washington sets the code statewide but leaves the fee schedule local, so two jurisdictions on the same edition can price the same project very differently. The electrical fee is the one that most often surprises people, because it is a separate city permit with its own fee. Ask Sammamish Community Development for the schedule in force on your filing date, and confirm the electrical route separately.

Fees are set locally, plus a small state permit fee (RCW 19.27.085); the electrical fee goes to whichever body issues the electrical permit. Permit fees in Washington

Trade permits and who may pull them

Plumbing and mechanical permits are local; electrical permits come from the Department of Labor and Industries unless the city runs its own electrical programme or Tacoma Power serves the site. Trade permits in Washington

How to apply for a Sammamish building permit

Review, corrections and what actually causes delay

In Washington the first cause of delay is the energy code, because the state code is its own instrument and more demanding than the international one most designers default to. After that comes critical areas review, which reaches ordinary residential work near wetlands, streams, steep slopes and shorelines and adds its own study and mitigation timeline. Then edition confusion around the switch-over date, when a new state edition takes effect and local amendments change with it. Build review time into the schedule and confirm the checklist with Sammamish Community Development before filing.

The state code sets a 180-day default for permit validity, but Sammamish may change it, so confirm the expiry on phased or delayed work. Permit validity in Washington

Inspections in Sammamish

Where a permit is required, standard checkpoints include footing and foundation, framing, rough-in plumbing and mechanical, insulation and energy code compliance, fire systems on commercial work, and final, with a certificate of occupancy before the building is used. On sites with erosion hazard areas, existing vegetation must be retained on the lots until building permits are approved, so clearing ahead of approval is itself a violation.

The city issues its own electrical permits, so electrical inspections are requested from the city rather than from the state.

Do not cover work before the required inspection has been approved. Keep the issued permits — plural — the approved plans and the energy code documentation available on site.

Sammamish permit search and official resources

Permit records in Washington are split the same way the permits are. Where Sammamish Community Development is the authority for the City of Sammamish, it holds the building, plumbing and mechanical records — and the electrical record too, because the city issues its own electrical permits and carries out its own electrical inspections. If you are buying, refinancing or renovating, check both, because a clean local record does not mean the electrical work was ever permitted.

These are the primary sources behind this guide. Codes, fee schedules and procedures change — confirm the position for your filing date.

• Sammamish applications and forms
• Sammamish Development Code 21.03.060, trees
• Sammamish Development Code 21.03.020, environmentally critical areas
• Sammamish single family residence submittal checklist
• Chapter 19.27 RCW, the State Building Code Act

Frequently asked questions

Do I need a permit to remove a tree?

In the R-1, R-4 and R-6 zones, yes, before removing any significant tree located on the lot. In the R-8, R-12 and R-18 zones the rule is expressed as retention instead: a minimum of 25 per cent of significant trees must be retained in areas unconstrained by critical areas and their buffers.

Is there any advantage to keeping a large tree?

Yes. Permanent preservation of a landmark tree receives retention credit at 200 per cent in some circumstances and 150 per cent in others, so preserving one can satisfy a materially larger share of the retention requirement than its own count.

Which trees are exempt from the retention calculation?

Significant trees determined to present an imminent danger, and significant trees located in public utility easements and public rights of way.

Can the city stop my work in winter?

It can. Construction draining to the lake during the wet season must provide water quality monitoring reports, and the director may halt wet season construction as necessary to protect the hazard area or prevent downstream impacts.

Which code edition applies?

The state edition as amended by the city. Washington has a mandatory statewide building code. The codes enumerated in chapter 19.27 RCW, the State Building Code Act, are adopted and amended by the State Building Code Council within the Department of Enterprise Services and are required in all cities and counties, so local government administers and enforces them rather than choosing whether to have them. The 2021 editions took effect on the fifteenth of March, 2024 after two delays, and the 2024 editions are dated to take effect on the third of May, 2027. The state adopts a new edition every three years and reviews the codes in two groups, but all of them take effect on the same date (the 2021 codes on 15 March 2024, the 2024 codes on 3 May 2027). A city or county may make the state code stricter but cannot opt out of it; local changes affecting houses or apartments need State Building Code Council approval, and the residential energy code cannot be changed locally.

Who registers my contractor?

The state. Most Washington contractors register rather than hold a licence; electrical and plumbing contractors must also hold an L&I contractor licence. Under chapter 18.27 RCW a contractor registers with the Department of Labor and Industries, files a continuous surety bond of $30,000 as a general contractor or $15,000 as a specialty contractor, and keeps liability insurance on file, renewing every two years. Registration is not a competence test and does not authorise trade work: electrical certification comes under chapter 19.28 RCW and plumbing under chapter 18.106 RCW. The electrical permit comes from the city, which runs its own electrical permits and inspections; elsewhere in Washington the Electrical Program at the Department of Labor and Industries (L&I) usually issues them.

Simplify Sammamish permitting with Alliance Permitting

Sammamish turns the canopy into arithmetic, which means it can be solved at design stage instead of argued at review. We solve it early.

Trusted by leading builders, developers, and national contractors — 21+ years of filing in the jurisdictions we write about.

Contractors and builders choose Alliance for Sammamish because the work is done by people who have stood at the counter:

• 21+ years of filing, so the edition and the electrical route are settled before submission
• We confirm which state code group governs each part of the work on your filing date
• State contractor registration, bond and insurance verified as active before filing
• Energy code and critical areas documentation prepared rather than discovered in review
• Two inspection queues sequenced so a cover-up never waits on the wrong inspector

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 Sammamish permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.