Attic & Roof Deck Insulation in Galveston, TX

Attic and roof deck insulation decides how much summer heat reaches a Galveston County home. With summer days regularly above 90F and nights around 80F on the island, a vented attic under a dark roof gets far hotter than outdoors. That heat radiates through thin insulation into the rooms below, and it heats any ducts and air handler sitting in the attic. There are two main ways to fix it.

Option one: seal and insulate the attic floor

For a vented attic with no ducts or equipment, the usual best value is to seal the ceiling and then add insulation on the attic floor. Sealing closes gaps around lights, fans, plumbing and wiring, the attic access and the tops of interior walls. Then we blow cellulose or fiberglass to the target depth. The Texas code summary lists R-38 for ceilings in Zone 2; the Department of Energy suggests R-49 to R-60 for an empty attic or adding R-38 to R-49 over 3 to 4 inches.

Option two: foam the roof deck

When ducts and the air handler are in the attic, spraying foam on the underside of the roof deck and closing the attic vents makes the attic part of the conditioned space. The ducts then sit in air close to indoor temperature, which cuts the heat they pick up. HomeGuide lists foam on the roof deck at $1,500 to $9,000. Open-cell foam is common for this; closed-cell may be used where extra vapor control or strength is wanted.

Things we check first

Before recommending either, we check the roof for leaks and damaged sheathing, look at bath and dryer venting, look for signs of pests and check the existing insulation for water damage. Storm damage and roof leaks are common on the coast, and insulation should never cover a problem.

Signs your attic needs work

Rooms that stay hot in the evening, an air conditioner that runs constantly, high summer bills, ducts sweating in the attic, or insulation you can see the joists through are the common signs.