Spray Foam Insulation in Indianola, IA

An older town than most of the metro

Indianola sits about fifteen miles south of Des Moines on U.S. 65/69, the seat of Warren County and home to Simpson College and the National Balloon Classic. Unlike the metro's growth suburbs, it has a substantial older housing stock: the Census Bureau's 2020-2024 American Community Survey shows about 20 percent of its roughly 6,500 housing units built before 1960, about 37 percent between 1960 and 1999, and a median year built of 1979. The blocks around the courthouse square and the college hold two-stories and bungalows from the 1890s through the 1920s.

Those houses were built with no insulation standard at all. Balloon-framed walls open into the attic, stone or brick foundations with a rim joist sitting on rubble, and attics with a few inches of rock wool added in the 1940s or 1950s are common. Ice dams and frost on the sheathing follow directly.

What an old Indianola house needs

Start in the attic: seal the open wall tops with rigid foam and spray foam, close the chimney chase with fire-rated material, cover any can lights, seal the hatch, then insulate to R-49 with baffles at the eaves. If knob-and-tube wiring is present, an electrician evaluates it first; we do not bury live knob-and-tube. In the basement, closed-cell foam over the irregular stone or brick wall and across the rim joist is one of the few insulation methods that conforms to that kind of surface and stays put.

Additions from the 1960s onward often sit on vented crawl spaces. Sealing the vents, covering the ground and foaming the crawl walls ties them into the house thermally.

The newer south and west sides, and the country around them

Indianola's 1990s and 2000s subdivisions on the south and west edges, about 31 percent of the stock built since 2000, have the familiar newer-house list: rim joist, bonus room, basement wall before finishing. And the farms and acreages around Indianola, toward Lake Ahquabi and the Middle River, have pole barns and shops where closed-cell foam on the steel stops the winter drip. We travel to Indianola regularly and scope house and outbuilding on the same visit when asked.