Kodiak Island Borough, AK Insulation Payback
Kodiak Island Borough attic insulation, by the numbers
DOE classifies Kodiak Island Borough as climate zone 7, very cold — a climate where the heating season stretches across most of the year. Its recommended attic R-value for bare joists is R-60. For an attic around 1,000 square feet, closing the gap from R-2 to R-60 costs around $3,480 and saves an estimated $2,225 a year — payback in roughly 1.6 years. Topping up the attic pays for itself fast here.
Heating vs. cooling in Kodiak Island Borough
Split it out and it's roughly $2,224 a year on the heating side, $1 on cooling. By estimated insulation savings, Kodiak Island Borough lands in the 91th percentile nationally. Zone 7 alone covers 120 counties in this dataset, and Kodiak Island Borough comes in 113th by savings. Alaska averages $2,854/year across the counties tracked here; Kodiak Island Borough comes in 22% lower.
Where these numbers come from
The heating and cooling degree days behind this estimate — 8,316 HDD and 7 CDD (base 65°F, 1991-2020 normals) — come from KODIAK AP, AK US, the nearest NOAA station with published normals, 53 miles from Kodiak Island Borough's center. By total degree days, Kodiak Island Borough sits at the 89th percentile nationally.
If the attic isn't bare
If Kodiak Island Borough's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-49. That smaller top-up costs around $2,280 and saves an estimated $325/year — payback about 7 years. Worth doing on the numbers alone.
Quotes and materials for this job
Real bids depend on how easy the attic is to reach and whether old insulation needs removing first, so treat $3,480 as a starting estimate for a Kodiak Island Borough job, not a quote. Expect at least a $600 minimum charge from most contractors.
Where these figures come from
Kodiak Island Borough's R-60 target and its degree-day figures both come from named federal sources - see the methodology guide for exactly which ones. The guide to what R-value actually means explains why R-60 is the target here specifically.