Washington Building Codes That Apply to a Kitchen Remodel

Washington adopts one set of building codes statewide, and cities and counties enforce it. For a kitchen remodel that means the same rulebook applies in Vancouver, Camas or unincorporated Clark County, with local rules covering permits and administration. This page lists the editions in force, explains how they apply to a remodel as opposed to a new house, and summarizes what each code asks of a kitchen. Electrical has its own page: kitchen electrical code.

Code editions in force as of October 2026

Washington does not use the IRC's own energy, plumbing or electrical chapters. WAC 51-51-003 hands those subjects to the state energy code, the UPC and the electrical rules.

Scheduled changes

• 2024 building codes. Not yet adopted. The State Building Code Council's schedule, revised 14 August 2026, sets the final adoption meeting for the residential, mechanical, fuel gas and plumbing codes on 16 October 2026 and for the energy codes on 20 November 2026, with an implementation date of Monday 3 May 2027. The Council's site states: "The effective date of the 2024 codes will be May 3, 2027." That date has been revised more than once.
• 2026 National Electrical Code. Adopted by Washington Labor and Industries effective 31 December 2026, applied by electrical permit issue date.

A kitchen permitted before 3 May 2027 is under the 2021 codes. If your project straddles either date, ask the permit office which edition your application will be reviewed under.

How the codes apply to a remodel

You are not required to bring the whole house up to current code. The rule for alterations (IRC R4504.1, in WAC 51-51-4504) is that the altered work must comply with the code for new construction and must not make the building less compliant than it was. The energy code says the same in its own terms: "Unaltered portions of the existing building or building supply system shall not be required to comply with this code" (R501.1.1).

Some requirements apply only to new construction. The energy code's credit system for heating equipment (R406) applies to new construction and additions, not to alterations, and does not list cooking appliances. And one requirement reaches beyond the kitchen: the alarm upgrade described below.

Ventilation

Washington's amendment to IRC M1505 says kitchens "shall include a local exhaust system", and sets the hood minimum by fuel: 160 cfm or 65 percent capture efficiency over an electric range, 250 cfm or 80 percent over a gas range, and 300 cfm for downdraft and other intermittent kitchen fans. A new or replaced hood has to meet those figures and must discharge outdoors through a duct (M1503.3). A hood able to exhaust more than 400 cfm needs makeup air only where the home has a fuel-burning appliance that is neither direct-vent nor mechanically drafted (M1503.6).

Whether Vancouver requires a hood to be added where none exists and only the range is swapped was not confirmed. Sizing, duct materials, termination distances and the recirculating-hood limits are on the range hoods and ventilation page.

Plumbing

The 2021 UPC applies as written for these kitchen items:

• Dishwasher air gap. A dishwasher may not connect to the drain or disposal "without the use of an approved dishwasher air gap fitting" (UPC 807.3). A high loop in the hose is not listed as an alternative.
• Traps and vents. Each fixture is separately trapped and each trap needs a vent (UPC 1001.2, 1002.2). S-traps are prohibited (1004.1).
• Island sinks. The UPC method is the island loop vent (909.1). No provision for air admittance valves was found in the text, so ask the plumbing inspector before designing around one.
• Shutoffs. A control valve goes immediately ahead of each water-supplied appliance (606.5).
• Disposals. The dishwasher drain may not connect on the discharge side of a disposal (419.2).

Sinks, faucets and plumbing explains what these mean for layout.

Gas

A gas range must be listed for household use and installed to the manufacturer's instructions (IRC G2447). Each appliance needs its own shutoff valve in the same room within 6 feet (G2420.5), and the flexible connector may not exceed 6 feet or pass through a wall, floor or cabinet partition (G2422.1.2). New gas branches are pressure tested (G2417.1.3). Moving or adding a gas line is permit work. The current legal status of gas appliances is covered in gas, electric or induction.

Energy

• Lighting. New lighting in the alteration must be high-efficacy (R503.1.4, R404.1). Replacing less than 10 percent of the fixtures in a space is excepted.
• Windows. A replacement window must meet a maximum U-factor of 0.30, and a skylight 0.50, for Vancouver's climate zone (R503.1.1.1, Table R402.1.3).
• Insulation. Exterior wall cavities exposed during the work must be filled: at least R-15 in 2x4 walls and R-21 in 2x6 walls (R503.1.1, Exception 2).

Structure and glazing

Altered structural elements must meet the structural provisions for new work (IRC R4504.4). Headers over openings in bearing walls are sized from the code's span tables (R602.7), and anything beyond those tables, including a beam carrying a concentrated load, must be engineered (R301.1.3). Removing part of an exterior wall or widening a window can also remove required wall bracing (R602.10). Whether the city asks for stamped engineering on every bearing-wall removal was not confirmed. Opening a kitchen wall goes through the process.

If a window or door changes, replacement glass in hazardous locations must be safety glazing (R4502.5.2). That includes glass in doors, and glass within 24 inches of a door where its bottom edge is less than 60 inches above the floor (R308.4).

Smoke and carbon monoxide alarms

This is the rule that surprises people. Where alterations requiring a permit occur, the dwelling must have smoke alarms as required for new dwellings (IRC R314.2.2): in each sleeping room, outside each sleeping area and on each story. Battery-powered alarms are allowed for this retrofit. Plumbing, electrical or mechanical work alone is exempt, so the trigger is a building permit, not a trade permit.

Carbon monoxide alarms are inspected on the same occasion (R315.2.2), with one difference: the trade exemption covers only nonfuel-burning work, so gas piping or gas appliance work is not exempt. Owner-occupied single-family homes legally occupied before 26 July 2009 are excepted from that inspection.

Clearances: code versus guideline

The National Kitchen and Bath Association's guidelines are recommendations, and their code notes are based on the 2015 IRC, so they trail Washington's current code. Use them for layout planning, not as a statement of what an inspector requires.

Where to go next

Codes say how the work must be built. Whether your project needs a permit, and which one, is a separate question answered in do you need a permit. JDI Construction designs to the adopted codes and handles permits for its clients as part of a Vancouver kitchen remodel.