“I have a builder friend who insists that houses need to breathe, meaning that they shouldn’t be built so tightly,” says Peter Yost of BuildingGreen in Brattleboro, Vt., and co-chair of the Products and Performance topic area for Vision 2020. “Every time he says it, I tell him that’s a myth.”
So is “heat rises” (in fact, hot air rises), another building science misnomer that Yost decries as hindering the progress of improving housing performance. “As an industry, we have to unlearn some things before we can move forward,” he says.
Here’s the true skinny on some well-heeled misconceptions:
- All buildings must face south (or north). While proper orientation to the sun is important, it should not be the only criteria in how a house is sited, says Rick Diamond, staff scientist at the Lawrence Berkeley National Laboratory. Access, views, surrounding buildings, and the proper treatment of glazing with respect to its different orientations, he says, should be part of a larger equation. “Energy criteria, important as they are in the design of buildings, cannot be dominating factors,” he says. “Sometimes it is important not to let the ‘energy tail’ wag the ‘design dog.’”
- Houses have to breathe. Simple rule: Build tight, ventilate right. There’s no doubt that a tightly built house without properly designed and maintained fresh-air ventilation is a potential indoor health hazard … just as it is equally true that a house with uncontrolled, temperature-driven air transfer through incidental leaks cannot be energy efficient. No doubt, spot and centralized ventilation needs to be right-sized and correctly installed and serviced, but an insulated and air-sealed envelope with a controlled fresh air exchange is the goal.
- More insulation will stop heat loss. Not without air sealing. The two should work in tandem; if you want to optimize the thermal resistance qualities of higher insulation levels, you have to block air transfer, too.
- Turning it “off” saves energy. Even in the “off” position, appliances and consumer electronics plugged into an outlet still draw energy, albeit a small amount per device. To maximize savings, install power strips or smartstrips, which can accommodate multiple products and truly shut off the flow of electricity when they are not in use—namely at night and when the house is unoccupied.