Spray Foam Insulation in Des Moines, IA

Spray foam insulation in Des Moines has two very different housing stocks to work with. Point2Homes' summary of Census data puts the city's median year built at 1961, with about 26.7% of its homes built before 1940, while suburbs like Ankeny and Waukee have median build years of 2006 and 2011. Winters are cold here too: Wikipedia's Des Moines climate table lists a January average low of 13.8F and about 36.5 inches of snow a season. We air seal and insulate attics, basements, rim joists, walls, garages and shops across the metro, using closed-cell or open-cell spray foam where it makes sense and blown-in insulation where it does the job for less.

What Iowa's code asks for

Polk, Dallas, Warren and Madison counties are all listed in Climate Zone 5A on OpenEI's county map. Iowa's residential energy rule adopts the 2012 IECC with state amendments, and its Table R402.1.1 sets these Zone 5 minimums: R-49 in ceilings; R-20, or R-13 in the cavity plus R-5 continuous, in wood-frame walls; R-30 in floors; R-15 continuous or R-19 cavity on basement walls and crawl space walls. New homes must also pass a blower door test at 4 air changes per hour or less. The same rule says remodeling or renovation of one- and two-family homes is outside the code's scope, so for an existing house those numbers are a target rather than a requirement. We write the target R-value next to each area on the quote either way.

Old city, new suburbs

A 1920s foursquare in one of the older Des Moines neighborhoods and a 2015 two-story in Grimes need different work. Older Des Moines houses often have balloon framing that lets warm air rise from the basement into the attic inside the walls, kneewalls in story-and-a-half homes, and only a few inches of settled insulation overhead. Newer suburban houses are tighter, but we still find bare rim joists all the way around the basement, cold bonus rooms over attached garages, and attic floors with gaps around recessed lights and bath fans. Our quote is built around the house you actually have.

Closed cell vs open cell

Open-cell foam is light and soft, rated about R-3.5 to R-3.7 per inch in HomeGuide's guide. It expands to fill a cavity and stops air well, but it lets water vapor pass, so in a Zone 5 house it needs a vapor plan. Closed-cell foam is rigid and dense, at R-5 to R-7 per inch, and at normal thickness it slows vapor and does not absorb water. In central Iowa that makes closed-cell the usual choice for rim joists, basement walls, roof decks with no vent space and steel buildings. Open-cell fits interior walls, some attic rooflines and sound control between floors. On open attic floors, we usually foam the gaps and blow cellulose or fiberglass on top.

Basements first

Most Des Moines area homes sit on a full basement, and the band of wood on top of the foundation is one of the leakiest spots in the house. The metro also knows water: Wikipedia records that the Des Moines Water Works was flooded on July 11, 1993, leaving 250,000 people without running water for 12 days, and a levee broke in June 2008. If your basement has taken water, we check it is dry and the source is handled before we insulate, and we lean on closed-cell foam because it gives water nothing to soak into.

Choosing among spray foam insulation contractors

When you call spray foam insulation contractors or insulation companies around Des Moines, or search for spray foam insulation near me, ask each one the same questions. What gets sealed before anything is insulated? Which foam goes where, and at what thickness and R-value? How will they handle attic ventilation and cold-weather spraying? How long should the family stay out while it cures (HomeGuide suggests 24 hours or more)? What happens to old, damaged insulation? A good company answers in writing. We do, area by area, so you can line our quote up against any other bid.

Spray foam insulation cost

HomeGuide's 2026 guide lists installed spray foam at $1.50 to $5.00 per square foot: about $1.50 to $3.50 for open-cell and $3.00 to $5.00 for closed-cell. Fixr's figures for an existing home run $3.15 to $7.50 per square foot. HomeGuide puts a rim joist job at about $2,000 to $2,500 and an average attic insulation project at $1,000 to $2,700. These are national ranges. Around Des Moines the age of the house moves the number most: pre-war attics often need cleanup and sealing first, while newer homes are usually quicker. We price your job after we see it, and the written estimate is what you pay.

Rebates

MidAmerican Energy serves much of the metro. Its 2026 Iowa residential rebate terms say qualifying work has to be bought and installed between January 1 and December 31, 2026, applications are due within 90 days of the invoice, and a prescriptive rebate cannot exceed 70% of the equipment cost, with labor excluded. Programs change every year, so check your utility's current list before you book, and keep your invoice. Get a free estimate

We cover Des Moines and Windsor Heights in the middle of the metro, West Des Moines, Clive, Urbandale and Johnston to the west and north, Waukee, Grimes and Adel out in Dallas County, Ankeny, Bondurant, Altoona and Pleasant Hill on the north and east sides, and Norwalk, Carlisle and Indianola to the south in Warren County. Des Moines and Windsor Heights have the most pre-1960 houses with open framing and thin attic insulation. Ankeny, Waukee, Grimes and Bondurant are mostly homes built since 2000, where the work is usually rim joists, bonus rooms and topping up attics. Each town page explains what is different there.