Frequently Asked Questions

HomeGuide's 2026 national range is $1.50 to $5.00 per square foot installed, with closed-cell at the high end. Fixr lists $3.15 to $7.50 per square foot for existing homes. Many small jobs hit a minimum of $1,000 to $2,000 or more. We give you a written price after we see the space.

It depends on the foam and the thickness. At HomeGuide's $1.50 to $5.00 per square foot, 1,500 square feet of surface works out to roughly $2,250 to $7,500 before any prep, removal or extra thickness. Attic floors are often cheaper with blown-in on top of sealed gaps.

Usually because of bad installs: foam sprayed over roof leaks or damp wood, foam that hides rot, or off-ratio foam that smells. The fix is careful prep, a dry surface, the right foam for the spot and proper curing time. We check for leaks and moisture first and tell you how long to stay out.

Iowa's energy code table sets R-49 for ceilings in Climate Zone 5, which covers Scott County. For an older house the code is a target rather than a requirement, since Iowa's rule leaves remodels of one- and two-family homes out of its scope. Most attics we see here are well short of R-49.

A 20x20 garage has about 400 square feet of floor, but you insulate walls and ceiling, which can be 1,000 square feet or more of surface. At HomeGuide's ranges, that is roughly $1,500 to $5,000 for closed-cell or open-cell foam, and small jobs often hit a minimum. We measure and quote it in writing.

Yes, once it is dry and the water source is handled. We use closed-cell foam on the rim joist and dry foundation walls because it does not soak up water. Any insulation that got wet in a past flood should come out first.

Closed-cell, at about R-5 to R-7 per inch according to HomeGuide, compared with R-3.5 to R-3.7 for open-cell. That is why closed-cell is used where space is tight, like rim joists and shallow roof bays.

It costs more per square foot, it is hard to remove later, and it needs careful installation and curing time. It is also overkill on a wide-open attic floor where blown-in does the job for less.

In heated basements, yes. Cold attics and unheated buildings need the surface and the foam within a working temperature range, so we add heat or pick a milder day.

Closed-cell foam slows vapor and keeps warm, damp air off cold surfaces where it would condense. It is not waterproofing and does not fix a leak, so leaks get repaired first.

Iowa's code table lists R-49 for ceilings in Zone 5. Most older attics here are well below that. We quote to that target unless you ask for more.

It removes the main cause, which is warm house air heating the roof deck. Combined with good insulation depth and open soffit vents, it usually solves the problem.

Not usually. If it is dry and clean, we seal under or around it and add on top. Wet, moldy or rodent-soiled insulation should come out.

Most single-family attics take a day. Larger houses or ones that need removal first can take two.

It is one of the cheapest ways to make a basement and the floors above it warmer. Most rim joists here are bare or stuffed with fiberglass that does not stop air.

Only after the water source is handled. Closed-cell foam tolerates occasional moisture better than fiberglass, but it does not stop water coming through a crack.

Foam in living spaces usually needs a thermal barrier like drywall, and some areas allow an ignition barrier coating instead. We explain what applies to your space.

In this climate a sealed, insulated crawl space with a ground vapor barrier usually stays drier and warmer than a vented one.

Cellulose settles some after install, so we blow a little extra to account for it. Fiberglass settles less.

Yes. We drill small holes, dense-pack the cavity and patch the holes. It works best in walls without fire blocking in the way, which we check first.

Per R-value on an open attic floor, yes, usually by a wide margin. Foam is worth it in tight spaces and on rim joists.

Usually 14 to 18 inches depending on the product. We set markers so you can check.

Yes, closed-cell foam on the steel keeps warm, moist air from touching the cold metal, which is what causes the drip.

Closed-cell foam bonds to clean, dry steel. We check for oil, rust and moisture first.

Rules vary by city and county, and heated or partly residential buildings may be treated differently from farm storage. Check with your local building office.

Yes. Many people insulate to keep the garage warmer or to protect the room above. Open-cell or blown-in can be enough.

Usually, yes. Wet fiberglass loses most of its R-value and wet cellulose mats down and can grow mold. It also keeps framing damp.

Most attics take a day. Larger or heavily soiled attics can take longer.

Do not disturb it. Have it tested. If it contains asbestos, a licensed abatement contractor removes it before we insulate.

Yes, but it is slower and costs more than removing loose fill because it is cut and scraped by hand.