Attic insulation plays a essential function in home energy performance. In fact, most building scientists agree that the attic should be the primary “target” space for insulation installation alamo and air-sealing upgrades. Most homes are built with code-required minimum ranges of attic insulation which might be far below current suggestions established by the U.S. Dept. of Energy.
Owners considering an attic insulation improve have a number of different insulation supplies to consider. Each attic insulating possibility has distinct benefits and limitations. Understanding these professionals and cons might help you choose the very best insulation upgrade for your attic.
Fiberglass batt insulation is popular because it is affordable and universally available. Regardless of age, many houses have attics insulated with fiberglass batts. The batts are typically installed between attic flooring joists, and unfaced batts are extra frequent than faced batts in attic installations.
PROS: More affordable than different sorts of attic insulation. Greatest type of insulation for DIYers to install. Unlike blown insulation, batts may be lifted up and moved to provide access to the ceiling below, can lights and ceiling-mounted vent fans. Present batt insulation can often be left in place when blown insulation is added to extend general R-worth in the attic.
CONS: Tough to put in appropriately round obstructions. Voids where insulation is missing contribute to important energy loss. A number of layers of batt insulation are required to attain really helpful R-values in most parts of the country; this makes it impossible to make use of the attic for storage except special platforms are constructed previous to insulation installation. Fiberglass insulation can’t stop air movement.
Two predominant kinds of blown (or blow-in) insulation are generally used: cellulose and unfastened-fill fiberglass. Both varieties are designed to be installed using particular blowing equipment.
PROS: Installation might be accomplished shortly and affordably. Blown insulation typically ends in extra full protection than is possible with fiberglass batts.
CONS: A thick layer of insulation (at the least 16 in. for northern components of the U.S.) is required, and this makes it inconceivable to use the attic house for storage unless special platforms are constructed prior to putting in the insulation. Cellulose and free-fill fiberglass insulation cannot stop air movement.
Skilled spray foam insulation contractors typically insulate an attic by making use of a thick layer of spray foam between the rafters. Two sorts of foam are used: open-cell and closed-cell. Opinions fluctuate as to which sort is best in an attic installation, however closed-cell spray foam is used extra frequently.
PROS: Closed-cell spray foam gives the very best R-value per in. (about R-6) of any attic insulation. It also creates an air and moisture barrier, so it eliminates the need for separate air-sealing work. Insulating beneath the roof deck as a substitute of on the attic flooring frees up attic area for storage and other purposes. This strategy additionally improves the efficiency of HVAC components (like air handlers and ductwork) located in the attic.
CONS: Most expensive attic insulation. A thick layer of foam utilized to the underside of the roof sheathing can trap moisture and cause sheathing to rot.
Rigid foam hasn’t been used as extensively for attic insulation until a most up-to-date development. In a single distinctive system, a proprietary inflexible foam panel is fixed to the underside of attic rafters, forming an air and thermal barrier.
PROS: Gives all the benefits of spray foam, with the extra benefit of sustaining attic ventilation. The potential for roof sheathing moisture damage is eliminated. The rigid foam is confronted with a radiant barrier that displays warmth for extra energy financial savings -one other advantage over spray foam.
CONS: The system is available in limited areas, so it isn’t as broadly available as spray foam. Installation cost is larger than fiberglass batts and blown insulation, but competitive with spray foam.