Yesterday I had the opportunity to visit the house of Lance Wright and his wife, built with the German “Passive House” standards as the ideal. It’s called a “passive house” because it relies on retaining natural heat in winter through “superinsulation,” rather than “actively” generating heat with an oil or gas furnace.
Buildings get astoundingly little attention from scientists and the public, given the fact that they are responsible for almost half of all carbon dioxide emissions in this country. If we’re going to cut our carbon emissions by 80% to deal with global warming (let alone oil and gas depletion), we have to achieve deep energy reductions in building energy use. Just insulating the attic and turning down the thermostat isn’t going to cut it.
Let me give you an idea of how well insulated this house was. Lance’s house has no furnace, yet it was 66 degrees F. downstairs and 70 degrees upstairs in the middle of a very cold December. In fact, there’s no additional heat generated in the house at all, except for the occasional electric space heater here and there in the house to take the chill off. (This electricity comes, by the way, from his solar panels.) His R-40 walls and south-facing windows take care of much of the heating requirements.
It’s amazing how little we know about this subject. The basic laws of thermodynamics have been known for several hundred years, but even today modeling a house’s resistance to heat loss is notoriously mathematically complex, even with a computer. The Passive House people have the best computer model in the world, although they’re still working on improving it and it’s still an art as well as a science.
Ask a conventional insulation contractor about all this and you’ll more than likely get a blank stare (if they even understand your question). Conventional insulation contractors do a good job of insulating your attic, blowing insulation into your walls, and replacing your leaky windows. This is certainly helpful, but they know virtually nothing about deep energy reductions of the kind that are necessary to confront our energy problems. To do that, we need more interest in and attention to the “superinsulation” of buildings as advocated by the Passive House institute.