Codes of Record

What applies to my job?

Pick the state and the product you build, install, or inspect. The card below answers from each state’s own record.

Residential energy storage systems in Washington

Which codes apply? In Washington, residential energy storage systems fall under the 2023 NEC, the 2021 IRC, the 2021 IFC, and the 2023 NFPA 855.

Wall or floor units at a one- or two-family home, about 5 to 20 kWh each, up to 80 kWh in a garage or outdoors. State record read Oct 24, 2026. Data as of Oct 26, 2026.

Codes that reach residential energy storage systems

The edition Washington enforces for each code that governs the product, and the part of the code that does.

  1. NECNational Electrical Code
    2023 NECVerified

    in force since Apr 1, 2024

    Where it reaches the product. Article 706, energy storage systems, with 705 for the interconnection and 710 for stand-alone operation.

    Electrical safety standards, administration, and installation (chapter 296-46B WAC), adopting NFPA 70-2023 · WAC 296-46B-010; chapter 19.28 RCW

    The 2026 NEC is adopted, not yet in force for December 31, 2026.

    The Washington NEC record
  2. IRCInternational Residential Code
    2021 IRCVerified

    in force since Mar 15, 2024

    Where it reaches the product. Section R328, stationary storage battery systems in dwellings.

    State Building Code Adoption and Amendment of the 2021 Edition of the International Residential Code (chapter 51-51 WAC) · WAC 51-51-003; WAC 51-51-008; chapter 19.27 RCW

    The 2024 IRC is proposed for May 3, 2027.

    The Washington IRC record
  3. IFCInternational Fire Code
    2021 IFCVerified

    in force since Mar 15, 2024

    Where it reaches the product. Chapter 12, energy systems, section 1207, which also points to NFPA 855.

    State Building Code Adoption and Amendment of the 2021 Edition of the International Fire Code (chapter 51-54A WAC) · WAC 51-54A-003; chapter 19.27 RCW

    The 2024 IFC is proposed for May 3, 2027.

    The Washington IFC record
  4. NFPA 855NFPA 855, Standard for the Installation of Stationary Energy Storage Systems
    2023 NFPA 855Verified

    in force since Mar 15, 2024 · Adopted directly

    Where it reaches the product. Chapter 15, one- and two-family dwellings and townhouses.

    State Building Code Adoption and Amendment of the 2021 Edition of the International Fire Code (chapter 51-54A WAC) · WAC 51-54A-1201.1; WAC 51-54A-1207

    The Washington NFPA 855 record

Washington laws that name residential energy storage systems

On the site: 13 laws, rules, orders, and bills, newest first.

Law or ruleKindStageDateWhat it does
WSR 26-10-069Washington State Register, WSR 26-10-069Code amendmentVerifiedPendingMay 5, 2026Proposes the 2024 International Fire Code as the state fire code. Source (opens in a new tab)
Chapter 173-905 WACWashington State Register, WSR 26-01-103RulePartialIn forceJan 16, 2026Requires producers of portable batteries to join approved stewardship plans from Jan 1, 2027, and adds medium format batteries in 2029. From Jan 1, 2028, retailers may not sell large format batteries without producer marking. Source (opens in a new tab)
ESSB 5445ESSB 5445 (2025 regular session), Chapter 265, Laws of 2025BillPartialIn forceJul 27, 2025Lets small solar arrays under 1,000 square feet, parking-lot solar canopies, and landfill solar skip state environmental review. Source (opens in a new tab)
Puget Sound Energy Tariff WN U-60Docket UE-240333TariffPartialIn forceJun 14, 2024Revises a utility's residential battery storage service schedule to remove limits on demand response participation and pay one enrollment incentive per battery. Source (opens in a new tab)
Chapter 19.95 RCWStatutePartialIn forceJun 6, 2024Requires licensed contractors and detailed written contracts for solar installations over $1,000, including costs, production estimates, and battery component details. Source (opens in a new tab)
WAC 296-46B-705Code amendmentPartialIn forceApr 1, 2024Requires anyone connecting a power source to the grid to consult the serving utility and meet its standards. Source (opens in a new tab)
WAC 51-51-0328Code amendmentPartialIn forceMar 15, 2024Requires home storage systems to be Listed to UL 9540 and labeled for residential use, except systems under 1 kWh. Source (opens in a new tab)
WAC 51-54A-1207Code amendmentPartialIn forceMar 15, 2024Requires storage systems above set thresholds, such as 20 kWh for lithium-ion, to be Listed to UL 9540, with spacing and location limits. Source (opens in a new tab)
Chapter 70A.555 RCWStatutePartialIn force–Requires battery producers to fund collection programs for portable batteries from 2027 and medium format batteries up to 2,000 Wh from 2029. Requires producer marking on large format batteries, those over 2,000 Wh or 25 pounds, from Jan 1, 2028, and studies their end-of-life handling. Source (opens in a new tab)
Chapter 80.60 RCWStatutePartialIn force–Requires utilities to offer net metering for systems up to 100 kW until the earlier of Jun 30, 2029, or a 4 percent cap. Source (opens in a new tab)
HB 1871HB 1871 (2025 regular session)BillPartialDid not pass–Would have offered incentives for grid-connected home batteries. Source (opens in a new tab)
SB 5727SB 5727 (2025 regular session)BillPartialDid not pass–Would have paid one-time incentives for home batteries in a utility time-of-use or virtual power plant program. Source (opens in a new tab)
SB 6008SB 6008 (2026 regular session)BillPartialDid not pass–Would have funded state grants to utilities for home battery incentives of up to $13,800 per low- or moderate-income customer. Source (opens in a new tab)

Every Washington law on residential energy storage systems, with filters

For information only. Your local building or fire official decides which code applies. We check state records often but can miss a recent change, so confirm with your official before you design, permit, or install. Terms of use