Injection foam wall insulation · Janesville, WI

Janesville homes were built to last. They weren’t built to hold heat.

The north and east side neighborhoods, the old GM-era ranches and two-stories, the brick and stucco homes near downtown — most of them have little or nothing in the walls. Cozy Walls fills them with injection foam from the outside, in a day or two, without touching a wall in your living space.

Erik lives in the area and does every Janesville estimate himself.

Why Janesville houses lose so much heat

It’s not bad construction — it’s the era. Most of the housing in Janesville went up between the 1920s and the 1970s, and Wisconsin builders of that time didn’t insulate walls the way we do now.

  • 1920s–50s homes near downtown and Fourth Ward: plaster over lath, siding over sheathing, and an empty cavity in between.
  • 1950s–70s ranches and split-levels on the north and east sides: either empty walls or cellulose that settled years ago and left a gap at the top of every stud bay.
  • Brick and stucco homes: the same empty cavity behind a heavier wall. We drill from the outside through mortar joints or stucco and patch to match.

The result is the same on every one of them: a furnace that runs from December to March and a house that still isn’t warm.

What we do in Janesville

Whole-home wall insulation

Every exterior wall filled with injection foam from the outside. Most homes in one day; two-story or over 1,400 sq ft in two.

The room over the garage

The cold bedroom or bonus room fixed by filling the walls around it and the garage below it.

Rim joist and basement walls

The leakiest spots in an older Janesville basement, sealed with foam.

Proof, not promises

Blower-door test and thermal scan before and after on every whole-home job.

What the day looks like

Real Cozy Walls jobs in Southern Wisconsin this month.

One row of siding off

As far as we open the house.

Foam in

Every cavity filled top to bottom.

Siding back on

You’d never know we were there.

What it costs in Janesville

Most whole-home projects run $5,000–$12,000 depending on the size of the house, before the $1,425 Focus on Energy rebate check* that we file for you. Military ($750**), first responder, teacher, and 60+ ($500**) discounts apply on whole-home projects. Show us a lower written quote for the same scope and we’ll beat it by $500. Erik gives you the number in writing at the estimate, and it’s good for 30 days.

*Focus on Energy is a Wisconsin program. Rebates are not available on Illinois homes.

**Discounts apply to whole-home projects with a minimum job size of $5,000. One discount per household.

Serving Janesville, Milton, Edgerton, Evansville, and Beloit.

Free estimate. Erik, the owner, comes out himself.

Get your free Janesville estimate

No pressure. No sales script. Just Erik and real numbers.

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