If you're comparing your energy bills to neighbors in similar-sized homes and coming up short, the difference is almost always insulation — specifically, wall insulation. Heating and cooling account for about half of a typical household's energy use, and in older homes without wall insulation, a significant portion of that energy is heating the outside air.
35%
of home heat loss occurs through exterior walls
15–25%
typical heating cost reduction after wall insulation
1 day
typical installation time — no renovation required
Why Walls Are the Biggest Energy Leak in Older Homes
Think of your home's building envelope as a container for conditioned air. The roof, walls, floor, and windows all play a role in keeping that air inside. But walls have the largest total surface area of any element — which means they're also the largest opportunity for energy loss when left uninsulated.
Homes built between 1950 and 1985 are the most likely to have empty wall cavities. During those decades, energy was cheap and building codes didn't require wall insulation in most jurisdictions. The result is millions of homes across the Pacific Northwest operating at a fraction of their potential efficiency — and homeowners paying the price every month.
A home without wall insulation is essentially a thin wood frame with drywall on the inside and siding on the outside — and nothing in between to slow heat transfer. When it's 35°F outside and 68°F inside, heat flows outward through every inch of that wall, relentlessly, all winter long.
How Much Can You Save?
The savings depend on your home's size, construction, and how much insulation you already have elsewhere. That said, homeowners who add injection foam wall insulation consistently report meaningfully lower heating bills — typically in the 15–25% range for heating season costs, with the largest impact in homes that previously had no wall insulation at all.
In the Pacific Northwest, the ROI on wall insulation is particularly strong. The climate features a long, cool heating season — October through April — and relatively mild summers that rarely require much cooling. That means you're paying to heat your home for six to seven months per year, and every improvement to wall insulation pays off across that entire season, every year, for the life of the home.
Other Benefits Beyond the Bills
Quieter Home
Wall insulation significantly reduces the transmission of outside noise — traffic, neighbors, rain on the siding. Homeowners frequently report this as an unexpected benefit they love.
Consistent Temperatures
No more freezing bedroom on the north side of the house. Insulated walls maintain more even temperatures from room to room and floor to floor.
Improved Home Value
Energy performance is increasingly a factor in home sales. An insulated home commands higher appraisals and attracts energy-conscious buyers.
Reduced HVAC Wear
When your furnace doesn't have to run as hard or as long to maintain temperature, it lasts longer and requires less maintenance.
Washington Utility Rebates That Offset the Cost
Washington homeowners may be eligible for utility rebates that significantly reduce the net cost of wall insulation:
$2.50
PSE (Puget Sound Energy) — per sq ft of wall insulation
Applied instantly at installation for eligible customers. We handle all paperwork as an approved PSE contractor.
$0.50
Snohomish PUD — per sq ft of wall insulation
Plus an additional $0.50/sq ft for pre-1976 homes with no existing insulation.
See full rebate details on our PSE & PUD Rebates page.
How Injection Foam Works
1
Drill
Small holes drilled through siding into each wall bay.
2
Inject
Foam expands to fill the cavity — around wiring, blocking, and framing.
3
Patch
Holes are professionally patched and caulked. Done in one day.
PSE customers can earn up to $2.50 per square foot in instant rebates — applied at the time of installation. On a typical home with 1,200 sq ft of exterior walls, that's $3,000 back before you even write the check.
