Frequently Asked Questions

Most of the bad stories come from poor installs: foam sprayed too thick in one pass, off-ratio mixes, foam over roof leaks, or attics sealed without thinking about ventilation and moisture. Some inspectors also want to see the roof deck. We follow the maker's application limits, fix leaks first and explain what foam on the roofline means for future inspections.

National guides put installed spray foam at about $1.50 to $5.00 per square foot. HomeGuide lists a whole house at $8,000 to $20,000 and roof-deck foam at $1,500 to $9,000. We quote your job in writing after measuring.

It is often a good fit. Foam on the roofline brings the attic inside the conditioned space, so ducts sit in much cooler air in summer. It costs more than adding blown-in on the floor, so we price both.

Closed-cell foam on the steel is the common choice because it stops condensation and adds R-value per inch. Living areas are usually framed and insulated like a house.

For Zone 4, the Department of Energy suggests R-60 in an empty attic, or about R-49 added over 3 to 4 inches of existing insulation. Many older attics here have far less.

Stay out of the work area during spraying and for the re-entry time the manufacturer lists, often about a day. Blown-in and crawl space jobs are usually less disruptive. We give you the timing before scheduling.

Where air leakage and hot attics are the problem, often yes. On a simple attic floor, sealing plus blown-in usually gives similar comfort for less money. We quote what fits your house.

Not usually. Foam has to bond to wood, steel or concrete. Old batts in the way come out first.

Not when it is installed correctly over dry surfaces with ventilation planned. Problems come from foam covering leaks or wet wood, which is why we check first.

Installed correctly and kept dry, it stays in place for the life of the framing it is attached to.

It often helps when ducts are in the attic, because the ducts lose less cooling. Results depend on the house, the HVAC system and duct condition.

A sealed attic is not vented to the outside, but it usually needs some conditioned air or dehumidification to manage humidity.

Open cell is common here and costs less. Closed cell can make sense where roof depth is limited or more vapor control is needed.

Some inspectors note that foam hides the roof deck. We provide photos and a written description of the work you can share.

Usually some form of drying: a dehumidifier or a small supply of conditioned air. We recommend one for your home.

No. It controls humidity and ground moisture. Water entering from rain or springs needs drainage work first.

Most homes take one to three days.

For damp, musty crawl spaces it often is. For dry crawl spaces, floor insulation may be enough.

Yes, and that is the easiest time. We coordinate with your builder so foam goes on before interior walls and finishes.

Closed-cell foam on the steel is one of the most reliable fixes for condensation.

Usually not. Foam needs to bond to the steel. Old blanket insulation typically comes off first.

We generally use closed cell on steel, because open cell lets moisture pass through to the cold panel.

Most attics are sealed and insulated in a day.

Yes, if the old insulation is dry and clean. We seal around it first.

A little. We install to the settled depth listed for your target R-value.

Per square foot, usually by a wide margin, which is why it is the standard choice for vented attic floors.

Not if it is clean and dry. Removal is for insulation that is wet, contaminated or in the way.

Most take one to two days, including reinsulation.

Usually yes. We contain the work area and route debris out through the attic or crawl space access.

Yes, but it is slow. Fixr lists foam removal at about $1.50 to $3 per square foot, up to about $5 when chipped off by hand.