Common Myths About Green Building
By Paul Eldrenkamp
Myth #1: You can succeed at being "green" without bothering to measure the impact of your actions.
I'm pretty sure what most people mean by "green" building is to build new or to remodel in a way that's more sustainable than business as usual. In turn, most definitions of "sustainable" would probably include the need to use less than before— less energy, less water, and so on. The only way to know if you're using less, though, is actually to measure how much you're using over time, and to note whether the trend line is heading in the right direction. Sadly, that rarely happens in the world of green building or remodeling. Most people have no idea how much energy they use in any given year in their home, or whether it was more or less than the previous year. There's almost no scorekeeping going on, in other words. If you don't keep score, how can you possibly know if you're winning?
Myth #2: "Green" is all about product choices.
Unfortunately, truly "green" building is not about all the cool stuff we can buy and put into our homes. It's mostly about the stuff we don't buy and put into our homes. Occasionally a community will have a local green homes tour, and we all get a chance to march from green house to green house and admire bamboo flooring, recycled glass tile, and roof-mounted PV systems. These are all good and noble things, but a true green homes tour would be pretty boring, as it would consist of visiting perfectly ordinary homes and admiring the very low utility and water bills of those homeowners who are particularly watchful against consuming too much of anything— and still somehow manage to live happy, fulfilled lives.
Myth #3: Geothermal is a green strategy.
"Geothermal" energy, strictly speaking, has to do with capturing very hot water from a few hundred feet under the ground and then using it to heat buildings or even generate electricity. You can find this sort of geothermal in Iceland, in New Zealand, and in parts of the Western US (think Old Faithful). You cannot, however, find it in Newton. In Newton, what we commonly call "geothermal systems" are more accurately referred to as ground-source heat pumps. Ground-source heat pumps heat and cool our buildings by taking advantage of the fact that, not too far below the surface, ground temperatures stay pretty reliably in the mid-50s. You need to understand, though, that ground-source heat pumps need to use electricity to do this—lots of electricity. They use this electricity to run the various pumps, compressors, and fans required to get the heat out of the ground and into your house (or, in the summer, to get the heat out of your house and back into the ground). So you may not be using gas or fuel oil directly to heat your house if you have a ground-source heat pump system, but here in New England the electricity that you are using to run the system mostly comes from gas, coal, fuel oil, and nuclear power plants. It may be true that a ground-source heat pump system is a good choice for your building; what's not true is that it's particularly "green."
Myth #4: A super-tight building can't truly be "green" because it will have poor indoor air quality.
It's certainly true that a super-tight house will have poor indoor air quality if it doesn't also have a well designed and installed ventilation system. The key to good air quality is good ventilation—a way of assuring that stale air in the house is replaced with fresh air at a steady rate. The fact, though, is that it's much easier to assure good ventilation in a very tight house than in a leaky house. A leaky house will typically be over-ventilated in the winter, leading not only to unduly high heating bills but also to uncomfortably dry indoor air. And in those periods in the spring and the fall when outdoor temperatures are close to indoor temperatures, a house that relies on random air leaks through the structure will often be under-ventilated. Look at it this way: You can implement a well-conceived ventilation strategy to provide fresh air to your house, or you can rely on the builder's mistakes. Which sounds better to you?
Myth #5: A "green" building is an environmental asset.
This myth gets promulgated in part because there are no awards given for leaving an empty piece of land empty. To achieve LEED-Platinum, for instance—possibly the highest honor in the US for a green building—you have to actually build a building. The problem is, there's nothing at all natural about a building—even a LEED-Platinum building. Think about it: We want a building to be warm when it's cold outside, cool when it's hot outside, light when it's dark outside, and dry when it's wet outside; of the millions and millions of species in the world, there's only a small select group we're willing to share our buildings with (dogs, cats, gerbils, goldfish, parrots, a few others); and, perhaps most telling of all, any sign of the most fundamental renewal force in the natural world— rot and decay—is the surest indication of failure in a building. A building is thus, at root, an attempt to keep nature at bay (and, in that vein, lawns serve as a sort of protective moat to aid that effort). Thus, it's a myth to think that buildings can ever be environmentally good; they can only be made to be a little less bad.