Four years ago when I trashed the Mainstream green McMansion, which even Bill McDonough praised "a new milestone in mainstream green construction," just about everybody thought it was a fine idea. It is remarkable to see how the ground has shifted so far since then. For example, over at Taunton Press blog Green Building Advisor, Martin Holladay wrote a post earlier this year that takes a position that is by most standards in green building, pretty radical.
He starts out by declaring indoor air quality, material choices and the VOC content of paint, all those subjects dear to TreeHugger, to be unimportant.
If you're building a new house, most of these topics turn out to be irrelevant. From an environmental perspective, the most important factor by far is energy use -- not energy efficiency, but actual energy consumption.
I happen to disagree with the relevance issue, but the "not energy efficiency, but actual energy consumption" is very significant; making a house 15% more efficient than the average house and then making it twice as big defeats the purpose. Efficiency is important as a means to reducing consumption, but the problem is consumption. So we should be measuring that, not the R-rating of the wall. That is why I have suggested that building codes should set absolute consumption limits rather than relative efficiency standards.
Holladay's advice for anyone thinking of building a new green home:
- The best approach is not to build. Since the number of people per household in the U.S. has been dropping for years, a strong argument can be made to support the proposition that the U.S. already has too many houses.
- It's better to renovate an existing building than to build new.
- It's better to live in a small house or apartment than a large one.
- To lower energy use, strive to improve the airtightness and insulation levels in the building where you now live.
And he concludes:
Of course, a perfectly reasonable argument can be made in favor of building a new house. But please don't call it sustainable.
I think this is part of a critical shift in the green building movement. Alex Wilson at Environmental Building News has demonstrated that transportation energy intensity trumps building energy efficiency by about 2.4 times and that where you build is a lot more important than what you build. (See also TreeHugger: Jargon Watch: "Transportation Energy Intensity" of Buildings). Kaid Benfield at NRDC Switchboard recently wrote a devastating post showing how 'the nation's first net zero energy community of custom designed homes" is a fraud. The smartest guys in the room are putting out the message that you have to look at the big picture, the absolute and total energy consumption.
Holladay has written an important post in a well-respected publication. I hope a lot of people read it. Spread the word about Green Building Advisor.
I do have one bone to pick with Martin: He suggests that material choices, indoor air quality, landscaping, and the VOC content of paint are irrelevant. But he also says that "to lower energy use, strive to improve the airtightness." I think that if you do that without worrying about indoor air quality, you are going to get a lot of sick people. We are tightening up houses without worrying about the buildup of toxic chemicals and VOCs in them, and if we treat this issue as irrelevant we are going to have sick houses the way we had sick buildings in the 70s, because we sealed them so tightly without worrying about air quality. You can't build a tight house without building a healthy house; material selection does matter.
More on Energy Consumption and Housing
Big Steps in Building: Change our Building Codes from Relative to Absolute
How Should We Really Measure Green Building?
9 "Green" Monsters: Can a 15,000 SF Mcmansion be Green?
Big Houses Are Not Green: America's McMansion Problem
This House Isn't Green