Spray Foam Insulation in Olathe, KS

Spray foam insulation in Olathe has to work in two directions. Wikipedia's climate summary for Olathe puts the average July high near 90F, with about 36 days a year at 90F or above, while the low dips below freezing on about 102 days a year and the records run from -29F to 114F. A house that leaks air loses cooled air in July and heated air in January. We seal those leaks and insulate attics, basements, walls and garages with closed-cell or open-cell spray foam, or with blown-in insulation where that is the better value.

Code and climate zone

Johnson County is in IECC climate zone 4A. The City of Olathe moved to the 2018 International Residential Code and 2018 International Energy Conservation Code on September 1, 2019. The 2018 IECC insulation table lists R-49 for ceilings in zone 4 and R-10 continuous or R-13 cavity for basement walls. For existing homes, ENERGY STAR recommends R-60 for a zone 4A attic with no insulation and R-49 added over 3 to 4 inches already in place.

Where Olathe houses leak

Olathe had 5,593 people in 1950 and 10,987 in 1960, when I-35 tied it to Kansas City; it reached 63,440 in 1990 and 141,290 in 2020, with 51,820 housing units. Most homes were built in the last 50 years: ranches and split-levels from the 1970s, two-stories with bonus rooms from the 1990s and 2000s, and newer subdivisions on former farm fields to the south and west. Even newer homes leak. The usual spots are the rim joist in the basement, recessed lights and bath fans, the attic hatch, top plates of interior walls, kneewalls and the floor of rooms over the garage.

Closed cell vs open cell

Closed-cell foam is dense, about R-5 to R-7 per inch according to HomeGuide, and it slows vapor and resists water. It is the right choice for rim joists, basement walls and other surfaces that touch cold or damp concrete. Open-cell foam, about R-3.5 to R-3.7 per inch, is lighter and less expensive per inch; it suits walls, kneewalls and roof decks where the vapor side is handled. For a wide attic floor, sealing the leaks and blowing cellulose or fiberglass to depth is usually the best value.

Basements and rim joists

Most Olathe homes have basements, and many owners finish them. Insulating the rim and walls with closed-cell foam before framing keeps the new space warm and keeps damp indoor air off cold concrete.

Questions for insulation contractors

When you compare spray foam insulation contractors or insulation companies near Olathe, ask what they seal first, which foam goes where, the thickness and R-value per area, how they keep the soffit vents open, how long you need to stay out after spraying (HomeGuide says at least 24 hours), and how old insulation will be handled. We put those answers on the quote.

Spray foam insulation cost

HomeGuide lists installed spray foam at $1.50 to $5.00 per square foot in its 2026 guide: $1.50 to $3.50 for open-cell and $3.00 to $5.00 for closed-cell. Fixr lists $3.15 to $7.50 per square foot in existing walls. A rim joist job runs $2,000 to $2,500 and a whole house $8,000 to $20,000 by HomeGuide's figures, and small jobs often hit a $1,000 to $2,000 minimum. After we measure, the written estimate is your price.

Evergy rebates

Evergy's Kansas rebate chart for residential insulation and air sealing lists $0.15 per square foot for R-38 ceiling insulation (up to $500), $0.04 per square foot for air sealing (up to $300), and $50 for insulating at least 50 linear feet of rim or band joist, under its Kansas Energy Efficiency Investment Act program running through December 31, 2027. Check the current chart and requirements before you schedule.

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We work in Olathe and the towns around it: Lenexa and Shawnee to the north, De Soto to the west, Gardner, Edgerton and Spring Hill to the south and southwest, Paola, Louisburg and Osawatomie in Miami County, and Belton and Raymore across the state line in Cass County, Missouri. Housing ranges from 19th-century homes in old county seats to new subdivisions on former farmland.