Frequently Asked Questions

HomeGuide's 2026 figures put installed spray foam at $1.50 to $5.00 per square foot, with open-cell at the low end and closed-cell at the high end. An attic runs $3,000 to $8,000 and a crawl space $2,000 to $4,000 in that guide. Access, thickness and removal change the total, and the written estimate after our visit is the price.

Most of the worry comes from poor installs: foam sprayed too thick in one pass, foam that covered a roof leak, or a sealed attic that was not planned with the HVAC system in mind. Lenders and inspectors also sometimes ask questions about foam on the roof deck because it hides the sheathing. A careful plan, the right thickness, and paperwork showing what was installed answer most of those concerns.

It costs more per square foot than fiberglass or cellulose, it is hard to remove once cured, and it needs the household out for about a day while it cures. It also seals a space so well that ventilation and moisture have to be thought through. Where those trade-offs do not pay off, we recommend blown-in or batts instead.

Usually because it was put in the wrong place or the wrong way: over a leak, too thick, mixed badly, or in a way that hid damage a buyer's inspector wanted to see. Removal costs $1.00 to $2.50 per square foot in HomeGuide's guide. Getting the plan right the first time is much cheaper.

Alabama's code summary lists R-30 for ceilings in Climate Zone 3. ENERGY STAR recommends R-49 for an uninsulated Zone 3 attic and an added R-38 if 3 to 4 inches are already there. We measure what you have and quote the depth needed to reach the target.

If the crawl space is damp, musty or has standing water, insulation alone will not last. A sealed vapor barrier, closed vents and sometimes drainage or a dehumidifier come first, and then the walls or floor get insulated. If the space is dry, insulating the floor above may be enough. We look and lay out both options.

On crawl space walls, rim joists and metal buildings, usually yes, because it slows vapor and does not absorb water. On a roof deck or in interior walls, open-cell often does the job for less. We price both where both could work.

Yes, and that is one of the main reasons people do it: it puts the ducts inside the insulated space. Your HVAC setup should be checked, since a sealed attic changes how the house handles air and moisture.

HomeGuide's guidance is 24 hours or more. For a detached shop or garage, the house may not be affected.

Closed-cell foam on the walls slows vapor and keeps humid air off cool surfaces, but the ground still needs a vapor barrier and any standing water has to be handled. Foam is one part of the fix, not the whole thing.

In a humid climate, a sealed, dry crawl space usually means fewer musty smells, less condensation on ducts and more comfortable floors. Whether it pays depends on how wet the space is now and how the HVAC is set up, so we look before recommending it.

A sealed crawl space needs some way to stay dry. In many houses that is a dehumidifier; in others it is a small supply of conditioned air. We size the approach to the space.

Yes, if the crawl space stays reasonably dry. Code calls for R-19 in floors in Zone 3. In a damp vented crawl space, floor insulation tends to get wet and fall, so we usually recommend fixing the moisture first.

Ask your pest control company what they need to see. Some prefer a gap at the top of foundation wall insulation for inspection. We leave the details they require.

Alabama's amended 2015 IECC-based code lists R-30 for ceilings in Climate Zone 3. ENERGY STAR suggests R-49 for an uninsulated Zone 3 attic.

If the old insulation is dry and clean, adding on top usually works. If it is wet, soiled by rodents or blocks air sealing work, removal first is better.

In most under-insulated homes, sealing and insulating the attic reduces the heat the AC has to remove. How much depends on the starting point, the ductwork and the equipment.

Most sealing and blown-in jobs take a day. Removal or a full roof-deck foam job can take longer.

To stop condensation, a modest layer of closed-cell bonded to the steel is often enough. For a building you plan to heat and cool, more thickness on the roof pays off. We write the thickness and R-value on the quote.

Yes, but anything below the work area needs to be moved or covered. Overspray travels, so we plan that with you before the day.

Closed-cell foam bonded to the underside of the steel keeps warm, humid air off the cold metal, which is what causes the sweating.

Rules vary by county and by how the building is used. Check with your local building office, especially if anyone will live or work in it regularly.

In attics, usually. It fills around wiring and framing without the gaps batts leave. Batts still work well in open walls during construction.

Some settling is normal and is accounted for in the depth installed. We blow to the settled depth for the target R-value.

Yes. Small holes are drilled in each stud bay, filled with dense-packed material, then patched.

HomeGuide lists $1.00 to $2.80 per square foot and an attic at $900 to $3,600. Your written quote is the price.

Not if it is dry and clean. If it is wet, soiled, moldy or blocking air sealing, it should come out.

Attic removal with a vacuum system runs the material straight to bags outside. We protect the path through the house and clean up after.

It should be removed, the area sanitized as needed, and entry points closed by a pest company before new insulation goes in.

Yes, though it costs more than loose fill because it has to be cut or scraped out.