Preparing a complete Washington State Energy Code residential submittal means accounting for both the base IECC framework and Washington's own state-specific amendments — missing the state-specific layer is one of the most common reasons an otherwise reasonable submittal gets flagged. This checklist walks through what to confirm before assembling a residential WSEC compliance package.
Verify which version of the Washington State Energy Code is currently enforced for the project's jurisdiction and permit date, since Washington updates on its own schedule that doesn't always align with the national IECC cycle.
Confirm whether the current cycle uses a straightforward prescriptive path, a UA trade-off performance approach, or a credit/points-based system allowing selection from a menu of efficiency measures — Washington's residential code has used different structures across cycles, and assuming the wrong one leads to an incorrectly structured submittal.
Pull insulation R-values for walls, roof/ceiling, floor, and foundation assemblies, along with window and door U-factor and SHGC data, directly from the current building plans and specifications rather than assumed values.
Check whether the current WSEC cycle includes specific provisions around heat pump systems, electric readiness, or other requirements beyond the base IECC — these need to be documented explicitly, since a Washington-specific reviewer will be checking for them.
Compile HVAC equipment efficiency and, where applicable under a credit-based system, confirm which specific measures are being claimed toward the overall compliance threshold.
Compare every input used in the compliance documentation against the architectural and mechanical plans in the same permit package — mismatches here are a common, avoidable source of review delays regardless of which compliance path is used.
Some Washington jurisdictions have additional local requirements or preferred documentation formats beyond the state minimum — confirming these before finalizing the submittal avoids an otherwise complete package being flagged for a local-specific omission.
Does the compliance path affect what documentation is needed?
Yes significantly — a credit-based system requires documenting which specific measures are being claimed toward the point threshold, which is a different documentation structure than a straightforward prescriptive or UA trade-off submittal.
How can I confirm which WSEC cycle applies to my project?
Check with the local building department or Washington's state energy code resources directly, since the applicable cycle depends on the permit date and can differ from what a similar recent project used if a cycle update has occurred since.
What's the most commonly missed item on this checklist?
Confirming state-specific amendment requirements beyond the base IECC — it's easy to document base IECC compliance thoroughly while missing a Washington-specific provision layered on top.
Psychro.Pro runs this same checklist internally when preparing WSEC residential compliance packages — accurate inputs, correct compliance path, and Washington-specific amendments accounted.Learn more.
