HVAC in Washington: the heat pump mandate that was removed, and the new cooling load

What does the Washington energy code require in 2026?

Energy credits, not a heat pump mandate. Most Washington HVAC pages get this wrong by describing a rule that was struck out of the code before it ever took effect.

Source fact: The current residential energy code is the 2021 Washington State Energy Code, chapter 51-11R WAC, adopted November 4, 2022 and effective March 15, 2024.

The State Building Code Council publishes it as “WAC 51-11R (Residential) 2nd Edition, 2nd Printing (Sept 2024)” and describes it as: “Based on the 2021 IECC.”

The Department of Energy’s Building Energy Codes Program records the same edition and the same effective date for both residential and commercial buildings.

Source fact: Between adoption and that effective date, the Council amended it.

WSR 23-21-105, filed October 18, 2023, was made to address preemption under the Energy Policy and Conservation Act of 1975 in the light of the Ninth Circuit’s decision in California Restaurant Association v. City of Berkeley.

The rule deleted section R403.13, the heat pump space heating requirement, and deleted section R403.5.7, the heat pump water heating requirement.

It also moved the baseline of the Table R406 credit system from a heat pump to a combustion heating system and redistributed the credits accordingly, adding further credit options.

HYRE HVAC Research Desk analysis: The distinction matters commercially and legally. Washington does not require you to install a heat pump, and a contractor telling you the state has banned gas furnaces is wrong.

What Washington has is a performance-credit code: a new or substantially altered home must accumulate a required number of energy credits from Table R406.

A home that heats with combustion has to make up the efficiency the heat pump baseline would have delivered from somewhere else — better envelope, better windows, a heat pump water heater, ventilation heat recovery. Gas remains legal. It is simply more expensive to comply with.

The useful next step: If you are building or doing a substantial alteration, ask your contractor which Table R406 credits your design is claiming and to show the total against the requirement.

That single sheet is what the permit reviewer will look at, and it is where a gas decision either pays for itself elsewhere or does not.

Does the DOE regional efficiency rule apply in Washington?

No. Source fact: 10 CFR § 430.32(c)(6) sets a national minimum for split-system air conditioners and then adds a higher, installation-enforced floor in two regions only: the Southeast (14.3 SEER2 under 45,000 Btu/hr) and the Southwest (the same, plus an EER2 floor of 11.7/9.8).

Washington is in neither. Its air conditioners are held to the national 13.4 SEER2, which is triggered at manufacture rather than at installation.

Source fact: And the correction that matters everywhere: the regional standard reaches air conditioners only. Heat pumps carry no regional installation standard anywhere in the United States.

Their floor is the national 14.3 SEER2 and 7.5 HSPF2 — in Washington, in Arizona, and in every other state. Our study of the regional split reads this out of the full CFR text.

HYRE analysis: The practical consequence for a Washington buyer is that the federal floor is low and does almost nothing for you.

HSPF2 — the seasonal heating efficiency measure — is where a Washington system earns or loses its money, and 7.5 is a floor, not a target. Equally important and not federally regulated at all: rated capacity at low outdoor temperatures.

A heat pump’s output falls as it gets colder, and the number that decides whether your house stays warm in January is the capacity at your design temperature, not the SEER2 on the brochure.

Our cold-climate performance study covers what that data looks like and where to find it.

Why do so few Washington homes have air conditioning?

Because until recently they rarely needed it. Source fact: EIA’s Residential Energy Consumption Survey 2020 records 52.5% of Washington households with air conditioning (52.5% ± 2.8 percentage points) — 50th of the 51 jurisdictions reported, and far below the national 88.7%. Washington’s household-weighted cooling load is 291 degree days against 4,793 heating.

Source fact: NOAA’s 1991–2020 county normals show the Cascades doing the work. King County, containing Seattle, records 80 cooling degree days and 6,290 heating.

Benton County, east of the mountains, records 744 cooling — about 9 times as much — and Okanogan County records 8,164 heating degree days.

Across 39 counties the median is 157 cooling and 6,319 heating degree days.

Source fact: Those normals cover 1991–2020, and they end just before the event every Washington homeowner now sizes against.

NOAA records that Seattle reached “108 on June 28 after reaching 104 the day prior” in late June 2021, and that “in the previous 126 years, Seattle had only hit 100 degrees three times. It reached that mark in three consecutive days in June!”

HYRE HVAC Research Desk analysis: This is why a 30-year normal is the wrong sole input for a Washington cooling decision, and it is an honest limitation of the degree-day figures on this page.

A normal describes a typical year; the reason Washington households are adding cooling is not the typical year but the tail.

A system sized only to 80 cooling degree days is sized for the season, not for the week that matters — and in a housing stock built for a climate without air conditioning, that week is also a health question rather than a comfort one.

Recommendation: Ask what outdoor design temperature the load calculation used and whether it reflects recent extremes rather than the 1991–2020 normal alone. Then ask what the system’s rated cooling capacity is at that temperature.

For a house with no existing ductwork — common in Washington’s older stock — a ductless heat pump usually answers both the heating and the cooling question with one machine, which is a materially different proposition from bolting an air conditioner onto a gas furnace.

What does it cost to run, and which licenses cover the work?

A heat pump heats for about $266 a year against $296 for gas, and two L&I licenses cover the work. Source fact: EIA’s 2024 residential averages for Washington are 11.90 cents per kilowatt-hour — 47th of 51 jurisdictions, among the cheapest electricity in the country — and $12.72 per thousand cubic feet of natural gas.

HYRE calculation: Applying the west census-region consumption averages from RECS 2020 Table CE3.1: a 95% gas furnace costs about $296 a year, a heat pump at a seasonal COP of 3.0 about $266, and cooling only about $244.

The breakeven seasonal COP is 2.70. The heat pump wins, but narrowly — Washington’s cheap hydroelectric electricity and cheap gas move together, so the running-cost margin here is smaller than in Arizona or Florida.

Washington ranks 20 of 51 on our Heat Pump Readiness Index.

HYRE analysis: Notice the third bar. Washington is the mirror image of the Sunbelt: heating is almost the entire bill and cooling is a rounding error.

So the efficiency money belongs on heating performance and on the envelope — and, uniquely among our eight states, the strongest financial argument for a heat pump here is often not the running cost at all but that it delivers cooling a furnace cannot, to a house that currently has none.

Source fact: Washington splits this work across two license regimes, and our store shows both.

Of the 1,223 Washington records verified against the Department of Labor & Industries' contractor license data on August 29, 2026, 760 are registered as “CONSTRUCTION CONTRACTOR — Heating/Vent/Air-Conditioning and Refrig (HVAC/R) (specialty SM)”.

463 hold an electrical contractor license in the HVAC/refrigeration specialty: 447 as “ELECTRICAL CONTRACTOR — HVAC/RFRG (specialty 6A)” and 16 as “ELECTRICAL CONTRACTOR — HVAC/RFRG-RESTRICTED (specialty 6B)”.

HYRE analysis: That split is not bureaucratic trivia. A ductless heat pump installation is substantially electrical work — a dedicated circuit, a disconnect, often a panel assessment — and in Washington the electrical side is licensed separately by L&I. The 6B “restricted” specialty is narrower again.

So the right question is not “are you licensed?” but “who is doing the electrical work, under which license?” If the answer is a subcontractor, ask for their license number too.

The useful next step: L&I publishes contractor license data openly. Look up the registration, confirm it is active, and check the bond and liability entries — Washington requires both, and both lapse.

What does our Washington contractor data cover?

Source fact: HyreHVAC’s store holds 1,223 Washington records verified against the Department of Labor & Industries' contractor license data, published through the Washington Open Data Portal and retrieved August 29, 2026. Each carries the issuing authority, the register checked and the date of the check. No Washington record failed verification.

What that is not: 1,223 records is 13.7% of the 8,930 verified records we hold across 8 jurisdictions, and it is not a census of Washington HVAC contractors.

It is not a ranking, and no company has paid for a position in it. Every national claim on this site rests on federal data — EIA, NOAA, the CFR — never on our own counts.

The useful next step: Verify any contractor yourself against L&I’s own record. Our licensing study explains what the eight state registers do and do not prove, including why “we could not verify this” and “this contractor is unlicensed” are different findings that must never be printed as the same one.