Attic insulation performs a critical role in home energy performance. In reality, most building scientists agree that the attic should be the first “target” space for insulation and air-sealing upgrades. Most houses are built with code-required minimal levels of attic insulation which can be far below present recommendations established by the U.S. Dept. of Energy.
Owners considering an attic insulation upgrade have a number of different insulation supplies to consider. Each attic insulating option has distinct benefits and limitations. Understanding these pros and cons might help you select the most effective insulation upgrade for your attic.
Fiberglass batt insulation is in style because it’s affordable and universally available. No matter age, many houses have attics insulated with fiberglass batts. The batts are typically installed between attic ground joists, and unfaced batts are extra common than faced batts in attic installations.
PROS: More affordable than different kinds of attic insulation. Greatest type of insulation for DIYers to install. Not like blown insulation, batts may be lifted up and moved to supply access to the ceiling beneath, can lights and ceiling-mounted vent fans. Current batt insulation can often be left in place when blown insulation is added to increase overall R-value within the attic.
CONS: Difficult to put in correctly round obstructions. Voids where insulation is missing contribute to vital energy loss. A number of layers of batt insulation are required to achieve advisable R-values in most parts of the country; this makes it not possible to make use of the attic for storage unless special platforms are built prior to insulation installation. Fiberglass insulation cannot stop air movement.
Two main forms of blown (or blow-in) insulation are generally used: cellulose and free-fill fiberglass. Each sorts are designed to be put in using special blowing equipment.
PROS: Set up might be accomplished quickly and affordably. Blown insulation typically leads to more complete protection than is possible with fiberglass batts.
CONS: A thick layer of insulation (no less than 16 in. for northern elements of the U.S.) is required, and this makes it unimaginable to use the attic house for storage unless particular platforms are built prior to installing the insulation. Cellulose and unfastened-fill fiberglass insulation can’t cease 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 differ as to which kind is greatest in an attic installation, however closed-cell spray foam is used extra frequently.
PROS: Closed-cell spray foam gives 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 as an alternative of on the attic flooring frees up attic house for storage and other purposes. This strategy also improves the effectivity of HVAC components (like air handlers and ductwork) located in the attic.
CONS: Costliest attic insulation insulation in concord. A thick layer of foam applied 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 till a most up-to-date development. In one unique system, a proprietary rigid foam panel is fixed to the underside of attic rafters, forming an air and thermal barrier.
PROS: Gives all the advantages of spray foam, with the extra benefit of maintaining attic ventilation. The potential for roof sheathing moisture damage is eliminated. The inflexible foam is confronted with a radiant barrier that reflects heat for added energy savings -another advantage over spray foam.
CONS: The system is available in restricted areas, so it isn’t as widely available as spray foam. Set up price is bigger than fiberglass batts and blown insulation, but aggressive with spray foam.