Frequently Asked Questions

The 2018 North Carolina Energy Conservation Code lists R-38 (or R-30 continuous) for ceilings in new work. For an existing Asheville home in Zone 4A, ENERGY STAR recommends reaching R-60 when the attic has no insulation and adding about R-49 when it already has 3 to 4 inches.

It costs more per square foot than fiberglass or cellulose, it is hard to remove once cured, and it needs a careful install: correct mix, correct thickness and time for the house to ventilate (HomeGuide advises staying out at least 24 hours). It also should not cover a leak or wet framing. Used in the right places, those downsides are manageable.

In the humid valleys around Asheville, a sealed and conditioned crawl space with foam on the walls usually keeps floors, ducts and joists drier than a vented crawl with batts in the floor. If the crawl space floods or holds standing water, the drainage has to be fixed first. We look before we recommend either.

National figures from HomeGuide run $1.50 to $5.00 per square foot installed, about $3,000 to $8,000 for an attic and $8,000 to $20,000 for a whole house. Steep lots, low crawl spaces and removal work change the total. We measure and send a written estimate, and that figure is the price.

Both have a place. Closed-cell goes on crawl space walls, rim joists, basement walls and roof decks where moisture is a concern. Open-cell fits interior walls and many attic rooflines where sound control and air sealing matter more than vapor control.

Yes, once it is dry and the wet insulation is out. Wet batts hold moisture against the floor framing, so they come out first. Then we can liner and seal the crawl space and foam the walls, after confirming water will not keep coming back in.

It depends on the target R-value and the space. Two to three inches of closed-cell is common on rim joists and crawl space walls. Roof decks and walls need more. We write the planned thickness on the quote.

Yes, in the right places. Crawl spaces, rim joists, attic bypasses and open walls during a remodel are good fits. Closed walls in an older house are usually better filled with dense-pack cellulose.

Installed correctly, it reduces them by stopping humid air. Problems come from foam over wet framing, the wrong foam in the wrong place, or an unvented attic with no plan for humidity. We plan around all three.

HomeGuide advises staying out at least 24 hours after spraying. We tell you when the space has cured and ventilated.

Usually some form of drying is needed, because a sealed crawl space is no longer flushed by outdoor air. That can be a dehumidifier or a small supply of conditioned air. We size it to your space.

Yes. Insulating the walls and rim and stopping drafts under the floor raises floor temperatures in winter, especially in rooms over the crawl space.

Often yes, though tight access adds labor. We check clearance during the visit and price accordingly.

A ground liner helps, but with open vents humid air still comes in. Full encapsulation seals the vents and insulates the walls too.

If you can see the tops of the ceiling joists, there is not enough. Uneven rooms, high bills and ice at the eaves on cold days are other signs.

Usually yes, if it is dry and clean. Wet, moldy or rodent-damaged insulation should come out first.

Most older houses leak far more than they need. If a house becomes much tighter, fresh air and combustion appliances should be considered, and we will point that out.

It can be, especially with ducts or equipment in the attic or a complicated roof. For a simple open attic floor, blown-in over sealed leaks is usually the better value.

Yes. Dense-pack cellulose is the usual method, drilled from outside under siding or from inside with patches.

Dense-pack and foam both reduce air movement. Drafts at windows, doors and outlets also need sealing.

Injection foams exist, but for most closed walls dense-pack cellulose is more predictable. We recommend foam where the framing is open.

Most houses take one to three days for walls, depending on size and access.

It depends on the material and target. Reaching about R-49 to R-60 usually means well over a foot of loose fill. We list the depth on the quote.

Some settling is normal and is accounted for in installed depth. Dense-pack in walls is packed to resist settling.

Yes, if the old material is dry and clean. Wet, moldy or contaminated insulation comes out first.

Per square foot, yes. HomeGuide lists blown-in at $1.00 to $2.80 per square foot versus $1.50 to $5.00 for foam.

Not if it is dry and clean. Wet, moldy, rodent-contaminated or flood-soaked insulation should come out.

Most attic or crawl space removals take a day. Larger or contaminated jobs can take longer.

Do not disturb it. Have it tested; if it contains asbestos, a licensed abatement firm handles removal.

Often yes, once the space is dry and any leak is fixed.