
Wall Insulation
Stop drafts, cut energy bills, and make every room comfortable with RetroFoam injection foam — installed from the outside, no remodel needed.
What is Wall Insulation with RetroFoam
Wall insulation with RetroFoam injection foam is the most effective way to insulate existing exterior walls without tearing apart your home. Unlike traditional fiberglass or cellulose, RetroFoam is a tripolymer-based resin that gets injected directly into enclosed wall cavities, filling every gap and void to create a continuous air seal.
According to the U.S. Department of Energy, proper wall insulation can reduce heating and cooling costs by up to 40% in under-insulated homes. For Minnesota homeowners dealing with extreme temperature swings, that translates to hundreds of dollars in annual savings.
Permanent air seal
RetroFoam never sags, settles, or loses its shape over time
No interior disruption
Installed from outside through small holes in siding
Year-round comfort
Eliminates drafts and cold spots in every room
Why Do Minnesota Homes Need Wall Insulation
Minnesota's climate puts extreme stress on homes. Winter temperatures regularly drop below zero while summer heat and humidity push into the 90s. Your walls are the largest surface area separating you from those extremes.
Most homes built before the 1990s have inadequate wall insulation — or none at all. Even homes with fiberglass batts lose effectiveness over time as the material compresses, sags, and allows air to pass through freely.
Drafty rooms and cold walls, especially in winter
Heating and cooling bills that keep climbing
Rooms that are too hot in summer, too cold in winter
Ice dams forming along the roofline
Noise from outside easily heard indoors
Outdated fiberglass that has settled or compressed

Benefits of Professional Wall Insulation
Lower Energy Bills
RetroFoam's air seal stops conditioned air from escaping. Most homeowners see a 15-50% reduction in heating and cooling costs.
Consistent Room Temperatures
No more hot and cold spots. Every room maintains a comfortable temperature because the envelope is properly sealed.
Reduced Outdoor Noise
The dense foam acts as a sound barrier, significantly reducing traffic noise and other outdoor disturbances.
No Moisture or Mold Risk
RetroFoam doesn't absorb water and doesn't promote mold growth, unlike fiberglass which can trap moisture inside wall cavities.
Lifetime Product Warranty
RetroFoam comes with a lifetime warranty. It won't settle, sag, or break down — your walls stay insulated permanently.
Minimal Disruption to Your Home
Installation happens from outside. No furniture moving, no drywall removal. Most homes are completed in a single day.
Our Wall Insulation Process
Siding Removal and Preparation
We carefully remove a course of siding to expose the wall sheathing beneath. Each stud cavity is located and a small hole is drilled. Our technicians use a specialized tool to check for obstructions inside the wall before injection begins.

RetroFoam Injection
RetroFoam the resin is mixed in the truck, then injected into each wall cavity through the drilled holes. The foam flows to fill every gap, crack, and void — wrapping around wiring, plumbing, and any obstacles. Pressure gauges ensure complete fill without over-packing.

Seal, Replace, and Verify
All drill holes are plugged and sealed. Siding is carefully replaced to its original position. We perform a final inspection to verify complete coverage and ensure your home looks exactly as it did before.

Wall Insulation Rebates and Incentives
Minnesota homeowners can significantly offset the cost of wall insulation through utility rebates and flexible financing. We handle the paperwork and help you maximize every available incentive.
40% of cost up to $1,200 each for attic and wall insulation, plus $600 for air sealing. Participating contractor required.
$1,500 wall insulation, $1,300 attic + air sealing combo, $200 rim joist add-on. Gas-heat customers; Rebate Eligible Installer required.
50% of cost up to $750 sidewall, $650 attic + air sealing, $425 foundation/rim joist combo. Authorized Insulation Contractor required.
40% of cost up to $1,000 attic, $1,000 wall, $800 air sealing — $2,800 annual cap per home. Electric primary heat required.
For qualified customers through our lending partners
For full details on available incentives, visit our rebates and incentives page. Not sure which utility serves your area? We'll help you figure it out during your free home assessment.