What is Washington Clean Buildings Act?

What it is

The law sets an energy use intensity target for each covered building based on its property type. Buildings above their target must take steps to reach it or follow the conditional compliance path the rules allow.

Alongside the target, owners must maintain an energy management plan and an operations and maintenance program, and benchmark the building. The Washington State Department of Commerce administers the standard.

Compliance dates are phased by building size, with the first group of the largest buildings starting in 2026. Coverage was later expanded to smaller commercial and multifamily buildings through a second tier with lighter requirements.

Who it applies to

Owners of nonresidential buildings at or above the size threshold in Washington State, including public and private owners. Check the Department of Commerce rules for the current thresholds, tiers and dates that apply to your building.

How it is measured

Compliance rests on measured energy use, normalized for weather, compared with the building's target.

• Twelve months of whole building energy use by fuel
• Weather-normalized site EUI
• An energy management plan and an operations and maintenance program
• Records of measures and their verified effect

How Aqueduct helps

Weather-normalized EUI per building is what aQ EnergySmart baselining produces, with verified reductions against the target.

• Weather-normalized site EUI per building, updated continuously rather than once a year
• The gap to target broken down to the systems and faults behind it
• Fault findings and operating records that support the operations and maintenance program
• aQ Assurance exports of measured data for the owner's submission