The R-value of spray foam trumps traditional insulation
Monday, October 22, 2012
If you keep topping-up your walls and ceiling in hopes of better insulation for your home, you’re going about it the wrong way. Adding layers of conventional insulation is not effective, experts say. Your insulation is not effective in the short- or long-term if it’s not done by a reputable company and with the right material.
Heat (and money) flows in or out of homes through convection — better known as air leakage. In fact, air leakage is the biggest source of energy loss in your home, accounting for as much as 40 percent. Insulation, such as fiberglass, allows air to pass right through, while spray foam blocks air flow.
Depending on your needs, a licensed installer will recommend either the 0.5-pound or 2-pound spray foam insulation. Foam insulation specialists tell us that the energy efficiency of R-value in combination with the air barrier of spray foam is vastly superior to that of traditional methods. Simply adding extra layers of fiberglass or cellulose to the interiors of your walls will eventually prove ineffective.
“Insulation that is compressed will not provide its full rated R-value,” according to data from the U.S. Department of Energy. “The overall R-value of a wall or ceiling will be somewhat different from the R-value of the insulation itself because some heat flows around the insulation through the studs and joists. Therefore, it’s important to properly install your insulation to achieve the maximum R-value.”
In addition, spray foam insulation requires less upkeep and lasts longer than traditional insulation.