As all builders know, constructing well-insulated building envelopes is critical for superior energy efficiency. In addition to high-performance materials and sustainable design techniques, the use of spray foam insulation can help builders and developers achieve airtight structures. This product is highly effective for sealing the cracks and crevices in a house or structure, thus greatly reducing air and heat flow. Indeed, the application of spray foam insulation can be an essential factor to a home’s energy-efficiency portfolio.
“For an ultra-high-performance home, or any structure that is utilizing passive solar design, spray foam insulation is a must,” says Jeffrey Dinkle, president of Atlanta-based Eco Custom Homes. “As an air sealer, it is simply the best product,” he says. “Although it may be a more expensive option, it is absolutely worth the cost when evaluated from a life-cycle cost perspective. Over the life of the house, it will pay itself back multiple times.”
Dinkle utilizes spray foam insulation in building high-performance custom homes that incorporate tight building envelopes. “When using this product, I know the full home cavity is going to be sealed and highly insulated,” Dinkle says. “Spray foam insulation works to close all gaps, down to the nail holes and even the openings around electrical boxes to ensure that the envelope is airtight. This promotes maximum energy efficiency and allows the HVAC systems to operate at peak efficiency.”
In addition to its high insulating qualities and superior air-barrier performance, spray foam insulation also contributes to healthier indoor air quality as well as better sound control, says Teresa Crosato, marketing communications supervisor with Icynene, a maker of environmentally friendly and 100 percent water-blown spray foam insulation.
Icynene offers both low- and medium-density spray foam insulation products for use in residential and commercial projects. Its LD-R-50, a Green Approved Product by the NAHB Research Center that exceeds the renewable content specification set by the USDA BioPreferred program, is a low-density, 0.5-pound spray foam insulation that provides enhanced moisture management and is ideal for use in residential and commercial construction. “One of the key benefits of the low-density (open-cell) spray foam insulation is that it is more of a breathable product and allows water to drain,” Crosato says. “This promotes drying so the original performance of the material is maintained.”
Another product, Icynene MD-R-200, is a 2-pound medium-density foam insulation made with recycled content that offers a high R-value and is appropriate for use in commercial construction due to its enhanced tensile and compressive strength. All of the Icynene products also feature blowing agents with the lowest Global Warming Potential—a measure of greenhouse gas emission potential—and are free from polybrominated diphenyl ethers (PBDEs). “They are a very healthy and green alternative for spray foam insulation,” Crosato says.
According to Dinkle, open-cell spray foam insulation works extremely well for a range of residential home applications. One section of the home where this product can be very effective is the attic. “In the Southeast, the attic can get as hot as 120 degrees in the summer. The current thought with high-performance homes is to condition this space by applying spray foam insulation to the roof rafters,” Dinkle says. “This creates an insulated thermal envelope and greatly reduces the heat pressure in the home.”
Yet another important area for open-cell spray foam insulation is the rim joists around the whole perimeter of the home. “Typically, rim joists are very difficult to insulate and can account for 20 to 30 percent of the air leakage in a home,” Dinkle says. “But also, rim joists are strong conductors of radiant heat and when they—or the attached decks—heat up from the outside, that heat can easily be transferred into the interior of the home. This can be seen through thermal imaging. Therefore, it is critical to use spray foam insulation at these locations in order to prevent air penetration and thermal bridging.”
In addition to open-cell applications, Dinkle says closed-cell spray foam insulation also has its appropriate uses. “Closed-cell insulation should be used in situations where it is desirable to fully eliminate air and vapor permeability,” says Dinkle. “This fits well for use in wine cellars or in the floors and ceilings of mixed-use projects. For example, if a residence is located above a street-level restaurant or café, it’s important to make sure that fumes and odors do not permeate through.”