Energy Efficient Spray Foam Insulation
Spray Foam Insulation is commonly used to construct insulation within structures, both commercial and residential. SPF is created from either synthetic or natural foam materials. The finished product is typically referred to as either polyurethane foam or expanded polystyrene foam (EPS). SPF is also sometimes called quilted foam or quilted membrane.
Spray polyurethane foam (SPF) is an adhesive spray-applied rigid foam that will form an air-tight seal and moisture-blocking barrier on the surface, walls, ceilings, all-around corners, and even on all curved surfaces. It’s made from a combination of liquid and solid polymer ingredients at the work area to produce durable foam. The essential elements include urethane and polymer mixtures mixed with curing agents to form a smooth, soft, pliable consistency. Other ingredients used in spray foam insulation may include silica, silicone, epoxy resin, fiberglass, and sometimes even vinyl to produce a smooth finishing product.
A spray foam insulation system consists of multiple layers, each providing an airtight seal and moisture blocking barrier. Many different spray foams have different densities, determining how much material can be included within the barrier. The most common materials used to insulate homes and buildings are polyurethane and fiberglass. Most spray foam insulation contractors will apply either one or the other to a structure. In cases where only one or the other is present, it’s possible to install one layer of insulation at a time. This is often accomplished with holes in the walls or ceilings and random places throughout a structure where the right-sized gap exists.
One method that many spray foam insulation contractors use is the R-value, which is a measurement of radiant heat transfer per square inch. Because a higher R-value means better resistance to heat flow, the thicker you can get your coverage, the better. The higher the R-value, the greater the resistance to heat flow, which means a lower energy bill. A higher R-value also means better insulation for the structure as a whole, because heat can travel through a more open cell structure.
When looking into heat transfer, you’ll typically find that R-values range from one to three. The higher the R-value, the better your resistance to heat transfer is. Higher values mean a larger barrier to prevent heat transfer. Some factors that affect the R-value include the number of air gaps between the walls and the ceiling and the type of surface on which the spray foam insulation is applied.
Another factor affecting the R-value per square foot is the method in which the spray foam insulation is applied. There are four types – cellulose fiberglass, expanded polystyrene (expanded polystyrene is also called bead board), spray foam battock, and spray foam foamed drywall. Cellulose fiberglass is the cheapest and least effective. Expanded polystyrene is superior to other forms, but is the most expensive. Spray foamed drywall and spray foam battock are both effective. These differences affect the cost per square foot, but not the overall effectiveness.
There are several ways to achieve a barrier, but one of the best ways is through an airtight seal. By sealing the walls in between the cells, there is little or no air leaks through the structure. Many times it’s not necessary to apply a vapor barrier if there is no existing air leaks, so air leakage is not a factor. With closed-cell spray foam insulation, the spray foam will form a closed cell when applied, creating an airtight seal. A moisture barrier can be used, as well, but it’s important that the area is sealed and maintained regularly to keep air from leaking out.
The final type is a highly effective moisture barrier. Expanded polystyrene is the best for this purpose because it’s thicker than cellulose but less expensive. It’s also more durable. If you’re looking for a very energy-efficient option, it’s highly effective in preventing heat loss and keeping energy bills low.