Attic insulation performs a vital position in dwelling energy performance. In reality, most building scientists agree that the attic needs to be the primary “target” space for insulation and air-sealing upgrades. Most homes are constructed with code-required minimal levels of attic insulation which can be far beneath current suggestions established by the U.S. Dept. of Energy.
Homeowners considering an attic insulation upgrade have a number of various insulation materials to consider. Every attic insulating option has distinct benefits and limitations. Understanding these pros and cons may help you choose the perfect insulation upgrade on your attic.
Fiberglass batt insulation is popular because it is affordable and universally available. No matter age, many houses have attics insulated with fiberglass batts. The batts are typically put in between attic insulation removal and replacement flooring joists, and unfaced batts are extra frequent than faced batts in attic installations.
PROS: More affordable than different forms of attic insulation. Greatest type of insulation for DIYers to install. Unlike blown insulation, batts will be lifted up and moved to supply entry to the ceiling below, can lights and ceiling-mounted vent fans. Current batt insulation can often be left in place when blown insulation is added to increase general R-value within the attic.
CONS: Troublesome to install appropriately round obstructions. Voids where insulation is missing contribute to significant energy loss. A number of layers of batt insulation are required to achieve really helpful R-values in most components of the country; this makes it not possible to make use of the attic for storage until particular platforms are built previous to insulation installation. Fiberglass insulation cannot cease air movement.
Two principal forms of blown (or blow-in) insulation are commonly used: cellulose and unfastened-fill fiberglass. Both varieties are designed to be installed utilizing special blowing equipment.
PROS: Set up may be accomplished shortly and affordably. Blown insulation typically results in extra full coverage than is possible with fiberglass batts.
CONS: A thick layer of insulation (not less than sixteen in. for northern components of the U.S.) is required, and this makes it inconceivable to use the attic space for storage unless particular platforms are built previous to putting in the insulation. Cellulose and free-fill fiberglass insulation can’t stop air movement.
Professional spray foam insulation contractors typically insulate an attic by making use of a thick layer of spray foam between the rafters. Two forms of foam are used: open-cell and closed-cell. Opinions differ as to which sort is finest in an attic set up, but closed-cell spray foam is used more frequently.
PROS: Closed-cell spray foam provides the highest R-worth 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 instead of on the attic ground frees up attic house for storage and different purposes. This strategy additionally improves the effectivity of HVAC parts (like air handlers and ductwork) located in the attic.
CONS: Most expensive attic insulation. A thick layer of foam applied to the underside of the roof sheathing can trap moisture and cause sheathing to rot.
Inflexible foam hasn’t been used as extensively for attic insulation until a most up-to-date development. In a single distinctive system, a proprietary rigid foam panel is fastened to the underside of attic rafters, forming an air and thermal barrier.
PROS: Supplies all the benefits of spray foam, with the additional good thing about maintaining attic ventilation. The potential for roof sheathing moisture damage is eliminated. The inflexible foam is faced with a radiant barrier that reflects heat for extra energy savings -one other benefit over spray foam.
CONS: The system is available in restricted areas, so it isn’t as widely available as spray foam. Set up value is larger than fiberglass batts and blown insulation, but aggressive with spray foam.