Most homebuyers hear the term “building envelope” in a sales presentation but pay little attention to it. CR Herro, vice president of environmental affairs for Meritage Homes, said that’s bad for the pocketbook.
“Most buyers know a lot about countertops and flooring, but they don’t understand that a [building] envelope could save you $50,000-worth of cost in heating and cooling,” he explained.
Defining the envelope
The building envelope includes the insulated walls in your home. That can range from the ceiling beneath your rooftop, walls that face the outside elements and even ones that separate a living room from the garage. Herro said it’s important to ask about insulation R-value (or thermal resistance — the higher the number the better), Low-E2 (low emissivity) windows and weather-sealed doors.
Today, many builders offer quality thermal-resistant materials standard with a new home. But Herro said that buyers should also be sure to ask about advanced framing methods that can result in big energy savings. Using two-by-six exterior walls, for example, allows for more insulation space, plus with advanced framing techniques, wall studs can now be placed 24 inches apart instead of
16 inches creating a wall cavity with far more insulation.
Sealing out leakage
Ken Peterson, vice president of sales and marketing for Shea Homes, emphasized how the building envelope must seal out any air leakage whatsoever.
The builder works to carefully seal all wall penetrations from things like plumbing or heating and ventilation. Ductwork is also properly sealed at the vents, a common spot for air leakage. “It’s a Thermos-bottle approach. We build very tightly sealed homes,” Peterson said.
Discussing the building envelope offers entrée into a more comprehensive energy-efficiency conversation. Once the buyer understands the importance of a tightly sealed building envelope, they are ready to talk about low-flow faucets, showerheads and toilets as well as other energy- and water-saving topics. “It’s about total consumption and reducing the carbon footprint,” Peterson said.