Frequently Asked Questions

HomeGuide's 2026 figures put installed spray foam at $1.50 to $5.00 per square foot, with closed-cell at the higher end. Rim joists alone run about $2,000 to $2,500 in that guide, and a whole house $8,000 to $20,000. Your written estimate after our visit is the actual price.

Mostly because of bad installs: foam sprayed too thick in one pass, foam that hid a roof leak, or a sealed attic that nobody planned around the furnace and ventilation. Inspectors and lenders may also ask questions when foam covers the roof deck. A careful plan, the right thickness and paperwork showing what went in answer most of those concerns.

Usually because it went in the wrong place or the wrong way: over a leak, too thick, mixed badly, or so that it hid damage an inspector wanted to see. HomeGuide puts foam removal at $1.00 to $2.50 per square foot, so getting the plan right the first time saves money.

Michigan's code table lists R-38 for ceilings in Climate Zone 5, and the Department of Energy recommends R-60 for an existing Zone 5 attic with little insulation, or adding R-49 over 3 to 4 inches. We measure what you have and quote the depth needed.

Usually yes. The rim joist is one of the leakiest and coldest spots in a Michigan basement, and closed-cell foam seals the gaps and insulates in one step without trapping moisture against the wood the way loose batts can.

Often. Dense-packed cellulose or injection foam can go into closed walls through small holes. We check for knob-and-tube wiring and blocked cavities first, since some walls are better left alone or handled from the outside during re-siding.

Closed-cell. HomeGuide lists it at R-5 to R-7 per inch, against about R-3.5 to R-3.7 for open-cell. It also slows vapor, which is why it is the usual choice for Michigan basements and rim joists.

Once cured and installed to the manufacturer's directions, it is inert. The concern is during spraying and curing, which is why HomeGuide advises staying out of the house for at least 24 hours and why we ventilate the work area.

Usually, yes. Foam plastic in living spaces, basements and garages generally needs a thermal barrier such as drywall, or an ignition barrier coating in some spaces. We plan that in the quote so there are no surprises at inspection.

Not as a rule. Foam needs to bond to clean framing or concrete, so old batts usually come out first. In an attic, new blown-in insulation can often go over the old after air sealing.

The residential energy code table lists R-38 for ceilings in Climate Zone 5, which includes Genesee County. That is for new work; the Department of Energy recommends R-49 to R-60 for existing attics in the zone.

It helps, but air sealing usually matters more. Ice dams come from warm air reaching the roof deck. Sealing the ceiling, insulating to depth and keeping the eaves vented together are what stop them.

Usually yes, if the old material is dry and clean and the ceiling has been sealed. Wet, moldy or rodent-soiled insulation should come out first.

Most Flint attics work best vented with a sealed, well-insulated floor. A sealed attic with foam under the roof deck makes sense when ducts or equipment are up there or the space is being finished.

In most older Michigan houses, yes. It is a small area that leaks a lot of air, and sealing it often makes the floor above noticeably warmer.

It depends on the product and how the basement is used. Many foams need a thermal or ignition barrier when left exposed. We tell you what your job needs and include it in the quote if you want.

Only after the water source is dealt with. Foam slows vapor but does not stop a leak or rising groundwater. Gutters, grading or a drain may need to come first.

Michigan's code table lists R-10 continuous or R-13 in the cavity for Zone 5 basement walls.

Usually yes, by drilling small holes and blowing dense-pack cellulose or injecting foam. We check for wiring and blocking first.

For closed walls, dense-pack cellulose is the common choice; for open walls during a remodel, spray foam gives more R-value per inch and seals air.

Not when the outside is shedding water and indoor air leaks are sealed. We check for signs of leaks or rot before filling.

Not always. We can work from inside or from under the siding, and re-siding projects make outside access easy.

It depends on how you heat and use it. Many heated shops get about 2 inches on walls and more on the roof. We size it to your goals and put the thickness in writing.

Closed-cell foam keeps warm, moist air off the cold steel, which is what causes the drip. That is the main reason people foam metal buildings.

Yes, but the space and the surfaces may need to be warmed so the foam cures properly. We plan for that in the quote.

Agricultural and accessory buildings are treated differently by different townships. Check with your local building department, and we can tell you what we have seen required.

If it is wet, moldy, smells, shows droppings, or has been smoke-damaged, it should come out. Thin but clean insulation can usually stay and be topped up.

Not until it is tested. If it contains asbestos, it needs a licensed abatement contractor; we can handle the reinsulating afterward.

Most attics take a day. Larger attics or foam removal take longer.

Sometimes. If air leaks are bad and the old material is in the way, clearing it makes thorough sealing possible.