Frequently Asked Questions

HomeGuide's range for about 1,000 square feet is $1,500 to $5,000, depending mostly on open versus closed cell and thickness. Fixr lists $3,150 to $7,500 for 1,000 square feet in an existing home, where access and prep add cost. We give you a written number after measuring.

Whole-house figures run $8,000 to $20,000 in HomeGuide's guide and $10,000 to $30,000 in Fixr's. Few Duluth houses need foam everywhere, though. Many jobs are foam on the rim joist and in tight spots, with blown-in insulation on the open attic floor, which costs less.

Mostly because of bad installs: foam sprayed too thick in one pass, poor curing, odor, or foam hiding a roof leak. Some home inspectors and lenders also want to see the roof deck, which foam covers. A correct install, the right foam for the surface and good records of what was done answer most of those concerns.

It can raise questions if there are no records. Keep the written scope, foam product and thickness for each area. Foam on rim joists, basement walls and walls rarely concerns buyers; foam on the underside of a roof deck draws more attention, so we discuss it before recommending it.

St. Louis County is in Climate Zone 7, where the 2012 IECC prescriptive table lists R-49 for ceilings. For an attic with little or no insulation, DOE suggests R-60 in Zone 7. Check with the city building office on code for a remodel.

Inside a heated basement, yes. Attics, garages and unheated buildings depend on the temperature, because foam has minimum surface and air temperatures to cure properly. We schedule those spaces around the weather.

Closed cell, in nearly every case. Basement walls and rim joists are cold and can be damp, and closed-cell foam slows vapor and does not absorb water. Open-cell can let warm indoor air reach the cold surface and cause condensation.

HomeGuide advises staying out for 24 hours or more while the foam cures. We will tell you the timing for your job, and ventilate the space while it cures.

Blown-in and batts cost less per square foot; HomeGuide lists blown-in at about $1.00 to $2.80 per square foot against $1.50 to $5.00 for foam. Foam costs more because it also air seals. Many jobs use both: foam where sealing matters, loose fill on the open attic floor.

Foam in living spaces generally needs a thermal barrier such as drywall, and the rules for attics and crawl spaces depend on how the space is used. We go over what your space requires before we quote it.

Air sealing does most of the work, with insulation and ventilation finishing it. Ice dams come from warm air melting snow on the roof. Seal the leaks, add insulation and keep the attic ventilated, and the roof stays colder. Heavy snow years can still produce some ice.

R-49 is the Zone 7 ceiling value in the 2012 IECC table, and DOE recommends R-60 when starting from little or nothing. We write the target R-value and depth on the quote.

On an open attic floor, sealing the leaks and blowing in loose fill is usually the better value. Foam on the floor costs $1,100 to $6,800 in HomeGuide's figures, and blown-in runs about $0.90 to $2.40 per square foot. Foam makes sense in tight spots and sloped ceilings.

Do not disturb it. Some vermiculite contains asbestos. It should be tested, and if it tests positive, removal is work for an asbestos abatement contractor. We will not cover it or remove it until that is settled.

It is one of the cheapest, most noticeable upgrades in an older house. The rim leaks a lot of air for its size, and sealing it often warms the floor above. HomeGuide puts a typical rim joist foam job at $2,000 to $2,500.

Often, yes, if it is dry. Closed-cell foam follows uneven stone. We check for water and loose mortar first, since foam should not trap water against the wall.

At typical thickness, closed-cell foam acts as its own vapor retarder, so a separate poly sheet over it is usually not needed and can cause problems. We will confirm what your wall assembly needs.

Yes. A heated basement is one of the easiest places to spray foam in January, since the temperature can be kept within the product's range.

Yes. Dense-pack cellulose is blown in through small holes drilled from outside or inside, then the holes are plugged and patched.

There are injection foams made for closed walls, but they are different products from open- and closed-cell spray foam. For most closed walls we recommend dense-pack cellulose.

In a house with empty walls, yes; it cuts drafts and cold surfaces. We look at the attic and rim joist too, since those are often cheaper and pay off sooner.

Have an electrician look at it first. Many insulation programs and codes do not allow covering active knob-and-tube without an evaluation.

That is the main reason people foam steel buildings. Closed-cell foam on the steel keeps warm, moist air off the cold metal, so the condensation has nowhere to form.

Only when the surface and air temperatures are within the foam's limits. That might mean waiting for a mild stretch or heating the building first. We plan for it in the quote.

It depends on whether it counts as agricultural and how your city or township treats it. Minnesota's State Building Code does not apply to agricultural buildings, with exceptions. Call your local office before work starts.

Foam in occupied spaces generally needs a thermal or ignition barrier, depending on the product and use. We go over what your building needs before quoting.

Not always. If it is dry, clean and not hiding air leaks that need sealing, new insulation can go on top. Wet, moldy, rodent-soiled or vermiculite insulation should come out or be tested first.

HomeAdvisor lists $1 to $2 per square foot and a typical job of $600 to $1,200. The written estimate after we look is the price.

It costs more than removing loose fill because it is cut or scraped off by hand. HomeGuide lists $1.00 to $2.50 per square foot and Fixr up to about $5 when it has to be chipped.

It is bagged or collected and hauled away for disposal. We include disposal in the removal line.