Why Seattle Homes Are Unique
Located in Climate Zone 4, Seattle homes deal with both winter heat loss and summer moisture load. Proper insulation helps stabilize indoor temperature across seasons.
The average residential electricity rate in WA is $0.11/kWh. In colder climates, attic heat loss directly increases utility bills and comfort complaints.
The Hidden Cost of Doing Nothing in WA
By the numbers:
- Annual Heating Degree Days (HDD):4000
- Annual Cooling Degree Days (CDD):1200
- High HDD values indicate the dominant seasonal load.
Zone 4 data shows that cooling load is the primary driver of avoidable energy waste. Upgrading attic insulation toward R-49 is one of the most direct ways to cut that load.
Cost vs. Value: Is It Worth It?
For a typical 1,000 sq. ft. attic in Seattle, a professional blown-in insulation upgrade often costs between $2520 and $3024, depending on labor rates and prep work.
With estimated yearly savings of $404, the project often pays for itself in 6.2 years.