There are some alternatives to the conventional fiberglass batt insulation. The options are non fiber glass batts, sprayed fiber insulation, sprayed foam insulation, and insulation blown or foamed through a membrane. The R- value of substance is indicator of its heat resistance. The R-values of most foam insulation products are higher than the R-values of batt insulation. This leads to the energy efficacy.
The spray foam can be used as an air sealant and insulator for the home walls, ceilings and cavities. Special equipments are used to spray the insulator into the wall cavities. After the insulator is sprayed it expands and fills the nooks and corners in the wall cavity. The extra foam from the studs is scraped to let form a uniform cavity of the wall. The wall cavities can be easily filled with the spray foam with the help of this insulator.
Two types of spray foams are available. The first type is open cell foam (isocyanurate) and the other is closed cell foam (polyurethane). The R-value of closed cell foams is higher than that of open cell foam.
The sprayed foam insulation is used as a liquid. This liquid contains a polymer (generally a polyurethane or urethane that is modified) and a foaming agent. A nozzle is used to spray the liquid in the cavities of the ceiling, wall and floor. Afterward this foam expands to fill every nook and cranny. The sprayed foam is supposed ideal for insulation of steel framing and the outlets because it expands into the tight areas also. Since it acts as an air barrier and heat barrier it positively eliminates the need for the air tightness detailing which is important for the higher efficiency. It also allows you to slim down the use of equipments used for heating and cooling. The foam insulations are not biodegradable and does not shrink, settle or sag.
Initial the cost of sprayed foam material appears greater than that of traditional fiberglass batt insulation. Since the sprayed foam insulation is insulator and an air barrier at the same time its cost is competitive with that of batt insulation. This insulation reduces some work like caulking, applying the house wrap, taping joints and vapor barrier. This certainly results in reducing the money you pay for specialized contractors. It even reduces the construction time. Since fiberglass batt insulation is labor intensive and cannot fit in window jambs, rim joist areas, around electrical boxes and small stud bays the spray foam insulation is preferred in such situations. Nearly all the spray foam insulators are eco friendly. Most of the do not contain the hazardous HCFCs, or harmful formaldehyde. The polyurethane insulation is more energy efficient in smaller spaces.
The installation of spray foam insulation requires some special equipment. It is better to contract a skilled installer. These products and services are readily available. The installation cost for sprayed foam insulation depends on the thickness of the wall and the type of the foam used.
Since certain companies provide a life time limited warranty it is better to heck with the manufactures before you decide installing spray insulation.