Attic Insulation & Air Sealing in Flint, MI

Attic insulation and air sealing are usually the best value in an older Flint home. Warm air rises and slips through every gap in the ceiling: around light fixtures, bath fans, plumbing stacks, chimneys, the attic hatch and the tops of interior walls. Once that warm air is in the attic it melts snow on the roof, which refreezes at the cold eaves as ice dams. Sealing those gaps and then adding insulation to the right depth cuts heat loss and helps stop the ice.

How deep is deep enough

Michigan's residential energy code table lists R-38 for ceilings in Climate Zone 5, which covers Genesee County. The Department of Energy goes further for existing Zone 5 homes: R-60 where the attic has little or nothing, or adding R-49 where 3 to 4 inches are already down. Many attics in 1940s and 1950s Flint houses hold a few inches of old rock wool or fiberglass that has settled and been disturbed by years of wiring and fan installs.

Sealing before insulating

Insulation slows heat moving through it but does not stop air. That is why we seal first: foam or caulk at top plates and wire holes, rigid board and foam around chases and chimneys (with proper clearance materials where needed), weatherstripping and an insulated cover on the hatch. Bath fans should vent outside, not into the attic.

Blown-in or spray foam

For most open attic floors, blown-in cellulose or fiberglass over a sealed ceiling is the cost-effective answer. Spray foam under the roof deck makes sense when there are ducts or a furnace in the attic, when the attic is being finished, or in tight spaces where loose fill cannot reach. In 1½-story houses, the kneewalls and short sloped ceilings often need foam because there is no room for anything thicker.

We will look in your attic, measure what is there and send a written quote. Get a free estimate