The term “high performance” likely conjures up an image of a car, one that's sleek and speedy, with an extremely powerful engine. The expectations surrounding such cars are high, which is why their allure is so strong.
“High performance” is a descriptor now being used in the home building industry, as well, and its proponents hope the term will evolve to the point where it evokes similar expectations. Like their vehicular counterparts, high-performance homes aren't characterized as much by their form as they are by their function.
“A high-performance home is one that has good measured indoor air quality and is comfortable [temperature-wise],” says Timothy Locke, a principal at Fair Oaks, Calif.–based Western Technical Associates, a building science consulting firm. “It has the same temperature everywhere in the house and has low energy bills.” Such a house, says Locke, may cost its owners as little as $400 per year in energy bills.
Architect Joseph Vigil, president of architectural firm VaST in Boulder, Colo., echoes Locke's description. He defines a high-performance home as one “that is very tight and doesn't lose a lot of energy through the walls and has a high-efficiency cooling system.”
ENERGY MISER: Chuck Miller Construction built this high-performance home to Building American standards using advanced framing, blown-in cellulose insulation, closed-cell foam sheathing over OSB, and sealed ductwork located in conditioned spaces. The house costs about two-thirds less to heat and cool per year compared to other houses in the neighborhood.
In short, a high-performance home is as energy efficient as a high-performance car is powerful and fast. It has features that are vastly superior to the average home—or even one built to model energy codes: a well insulated shell, tight construction, energy-efficient windows and HVAC system, and clean indoor air.IS IT GREEN?
Builders and consultants agree that high-performance homes by definition reduce fossil-fuel usage and keep their inhabitants comfortable, which many claim qualifies these homes for green status. However, Vigil says, and many others agree, that high performance is only one component of a three-legged, green, home design stool that building pros should consider.
“[High-performance building] usually has to do with energy, but it's not necessarily about green,” Vigil explains. Green construction, he says, is broken down into three areas: being mindful of the natural environment, building to high-performance standards, and being socially conscious. “It's possible to incorporate all three in a house, but they may not go hand in hand.”
Vigil says, for example, that concrete is considered by many people to be a green material—especially if it contains fly-ash waste from power plants—but it takes a lot of energy to produce the material. The same goes for solar technology.
CRAFT MADE: Hedgewood Properties' EarthCraft houses feature cellulose or sprayed foam insulation, solid drainage planes on the exterior walls, and an advanced air sealing system that reduces pollutant infiltration. Each house is independently tested (including blower door analysis) by a third party to verify that it meets high-performance standards.
It's true that a fully sustainable or green house considers many issues, from the way materials are sourced and manufactured to life-cycle analysis; converting your company to one that does fully sustainable houses is a serious undertaking. But interested builders must start somewhere, and because energy efficiency often accounts for half of the points in many green building programs, a high-performing, energy-efficient home is a good place to begin.
Building high-performance homes that have a strong emphasis on energy efficiency has been the strategy of builder Chuck Miller, president of Hidden Springs, Idaho–based Chuck Miller Construction, which builds about 12 high-performance homes a year. “My buyers pay about two-thirds less than their neighbors to heat and cool their homes,” Miller says. “They pay about $1,200 [a year] for gas and electric, while their neighbors pay about $3,600.”
So what exactly does high-performance construction entail, and how do you go about building a durable house that uses less energy?