Attic Insulation & Air Sealing in Asheville, NC

Attic insulation and air sealing usually go together. Warm air rises, and in an Asheville house it escapes through every gap in the top-floor ceiling: around plumbing vents, chimney chases, recessed lights, bath fans, the attic hatch and the top plates of interior walls. Adding insulation over those gaps without sealing them leaves the leaks in place. We seal first, then add depth.

What R-value your attic needs

The 2018 North Carolina Energy Conservation Code lists R-38, or R-30 continuous insulation, for ceilings in new construction. For existing homes, ENERGY STAR sets a higher target in Zone 4A, where OpenEI's county list places Buncombe, Henderson, Haywood and Madison counties: reach R-60 if the attic has no insulation, or add about R-49 if 3 to 4 inches is already there. Many older attics around Asheville have far less, sometimes a few inches of settled fiberglass that has been stepped on for decades.

Blown-in or spray foam?

There are two common approaches. The first keeps the attic vented and treats the attic floor: seal the bypasses with foam and caulk, then blow cellulose or fiberglass to depth. For most attics with a reasonable floor, that is the lower-cost route. The second moves the insulation to the roofline with foam under the roof deck, making the attic part of the house. That suits attics with ductwork or equipment in them, vaulted ceilings and complicated roofs with little floor space. We explain which one fits and price both if both would work.

Kneewalls, bonus rooms and hatches

Many homes here have rooms built into the roof: upstairs bedrooms with sloped ceilings and short kneewalls, and bonus rooms over garages. These are common trouble spots. The space behind a kneewall is often open to the floor joists below, so air runs straight under the room. We seal and insulate the kneewall, block the joist bays, and insulate the sloped ceiling where it can be reached. Attic hatches and pull-down stairs get weatherstripped and insulated covers.

Ventilation still matters

A vented attic needs clear soffit vents and a path for air to the ridge or roof vents. Before blowing insulation to depth, baffles go in at the eaves to keep the vents open. Bath fans that dump into the attic get pointed outside. Those details keep moisture from building up in the attic in winter.