Washington State Energy Code was updated for homes permitted on or after February 1, 2021. The new code requires improved energy performance for new homes.
Meeting the new energy code isn't hard or inexpensive; it just takes some careful building techniques and slight efficiency upgrades. Air sealing is important, as is better insulation.
A few examples of how the code changed from the previous energy code: a new home must now achieve insulation levels of R-60 in the attic (up from R-49) and R-38 in the floor (up from R-30). Heat pumps must have a HSPF of 9.5 instead of 9.0. These energy-efficient improvements will help you use less energy at home for many years.
Here is an example of how you could meet the current energy code requirement by earning 6 credits: