Frequently Asked Questions

National figures from HomeGuide put installed spray foam at $1.50 to $5.00 per square foot, with attics at $3,000 to $8,000 and whole houses at $8,000 to $20,000. Foam type, thickness, access and whether old insulation must come out change the number. We give you a written estimate after seeing the house, and that estimate is the price.

Closed-cell foam, at roughly R-5 to R-7 per inch according to HomeGuide, compared with about R-3.5 to R-3.7 for open-cell. Higher R per inch does not always make it the right choice, though. Under a roof deck, open-cell at the right thickness often does the job for less, while closed-cell earns its cost in crawl spaces and anywhere moisture is a risk.

Foam itself is not food for mold, but wood or drywall that stays wet can grow it, foam or not. Mold problems usually trace back to a roof leak, a plumbing leak or humid air reaching a cold surface. That is why we look for leaks before spraying and why crawl space and attic encapsulation in Birmingham includes controlling the humidity in that space, not just insulating it.

Alabama's amended 2015 energy code, as summarized by Alabama Power, lists R-30 for ceilings, and it treats R-20 of spray foam as equivalent in a sealed, semi-conditioned attic. For existing homes, the Department of Energy recommends R-49 to R-60 in a Zone 3 attic that has no insulation. Check with your city's building department on permits for your project.

If your ducts and air handler are in the attic, sealing it with foam on the roof deck usually makes the biggest difference in comfort and keeps the ducts from sweating. If the attic is empty of equipment, sealing the attic floor and blowing insulation to depth often costs less. We look at both and price them side by side when either would work.

HomeGuide advises staying out for at least 24 hours after spray foam is applied, and we plan jobs around that. Blown-in cellulose or fiberglass work does not require you to leave. We go over the timing for your job when we schedule it.

For the underside of a roof deck, open-cell is the more common choice here. It costs less, fills rafter bays well, and lets a roof leak show itself instead of trapping the water. Closed-cell makes more sense where moisture or limited depth is the issue.

Not on top of loose fill or batts in a way that does any good. Foam has to bond to the surface it seals. We remove or pull back old insulation where the foam needs to go, and list that work on the quote.

Foam closes many gaps insects use, but termites can tunnel through it and it can hide their mud tubes. Alabama is in HUD's very heavy termite zone, so we leave the inspection areas your pest control company needs and talk with you about your termite contract before foaming a crawl space.

A tighter house is the goal, but it does need controlled fresh air and safe venting for gas appliances. We check for combustion appliances in the spaces we seal and tell you if ventilation changes are worth discussing with your HVAC contractor.

When the ductwork and air handler are in the attic, sealing the roofline usually cuts the heat they pick up and the cooled air they lose. How much you save depends on the house, the ducts and how you run the system, so we do not quote a percentage.

Some shingle manufacturers have rules about unvented roof assemblies. Check your shingle warranty terms or ask your roofer before you decide, and we will plan around what it says.

It is not required, but once the roofline is sealed the floor insulation does little work. Many owners remove it, especially if it is dirty or has rodent damage. We price it as a separate line.

It can if it is left completely on its own. A sealed attic is part of the house, so it usually gets a small supply of conditioned air or dehumidification. We discuss the options with you before the job.

In a humid climate, a vented crawl space often stays damp most of the summer, and sealing it is the most direct way to keep the framing and ducts dry. Whether it is worth the cost for your house depends on how wet it is now and how long you plan to stay. We give you the facts and the price.

Usually some form of drying is needed, either a dehumidifier sized for the space or a small supply of conditioned air. Without it, moisture from the house and the foundation can build up. We include the option on the quote.

It can. Some pest control companies have rules about foam or liners in crawl spaces. Call your company before the work, and we will leave the inspection gap they need.

Yes, if the crawl space is reasonably dry. If batts fell because they got wet, putting new ones up without dealing with the moisture means the same thing will happen again. We tell you which situation you have.

Yes, if the existing insulation is dry and clean. We seal the gaps first, which sometimes means moving the old fill aside, then blow new insulation over it. Wet, moldy or rodent-soiled insulation should come out first.

Most single-family attics take a day or less, including air sealing. You do not need to leave the house, though we keep the attic access area covered and closed while we work.

If the attic has no ducts or equipment, blown-in over a sealed attic floor usually costs less for similar results. If the air handler and ducts are up there, sealing the roofline with foam often helps more. We price both when either would work.

Some settling is normal, more with cellulose than fiberglass. We install to the depth that delivers the stated R-value after settling and mark that depth in the attic.

Yes. Dense-pack cellulose and injection foam both go in through small holes in each stud bay, drilled from outside or inside. The holes are plugged and patched when we finish.

Pull the cover off an outlet on an exterior wall and look with a flashlight, or we can check a few cavities during the visit. In very old Birmingham houses, empty walls are common.

It costs more than batts, but it fills the cavity completely and seals the gaps around wiring and plumbing, which helps new homes pass Alabama's blower door test. We price foam and alternatives so you can compare.

Usually, working from inside through small holes or during a remodel. Brick veneer has an air gap behind it that should stay open, so we fill the stud cavities only.

Not always at once, but an attic or crawl space with nothing in it will make the house much harder to heat and cool. Most people remove and replace in one job, which also lets us seal everything while it is exposed.

We do not recommend it. Soiled insulation carries smells and contaminants, and its R-value drops where it has been tunneled or compressed. Removing it also lets us find and seal the entry points.

Leave it undisturbed and have it tested. Vermiculite can contain asbestos, which must be handled by a licensed abatement contractor. We can insulate after it has been cleared.

Attic removal is done with a hose that runs from the attic to the outside, and we cover the path through the house. Some dust is possible around the attic access, and we clean that area before we leave.