Met Eco (continued)
—
MH: It’s hard enough to be green when you’re building from the ground up and can control every element. Isn’t green renovation even more difficult?
Gitt: Yes, but only because renovation, whether green or not, is harder than building from scratch. There are always surprises when you open up a building.
Harrison: Sealing a house properly is the most cost-effective way to reduce energy use. And it’s hard to seal a house properly when you’re renovating.
Freed: Another problem with renovation, as opposed to new construction, is that you’re stuck with how the house is sited. Most houses are built parallel to the street; they don’t account for the fact that the sun is going to rise in the east and set in the west. That’s why, when we add on to existing houses, we often angle the addition toward the sun, which puts a crook in the floor plan. It’s become a kind of trademark.
Photo: Organic Architect
MH: Contemporary houses often have a lot of glass, but isn’t glass a problem when it comes to insulation?
Gitt: With the right design, you can still have glass. You can use it to maximize the solar gain during the day. Heat is stored in a thermal mass, which can be something as simple as a concrete slab or tile floor. The heat radiates back into the building at night.
Harrison: Depending on location! This technique doesn’t work in Seattle. And windows lose heat anywhere from five to ten times as fast as walls.
MH: WHAT ABOUT IN L.A., WHERE THERE IS SOMETIMES TOO MUCH SUN?
Shaw: I’ve used low-E glass in a number of projects. The low-E coating, which is invisible, lowers the heat flow through the glass. There’s a noticeable difference in temperature and comfort.
MH: Everyone talks about sealing the house to save energy. But doesn’t sealing the house trap indoor air pollutants?
Harrison: Yes. So if you tighten the house, you also need to ventilate it properly and use healthier materials inside the house so they don’t off-gas and contribute to indoor air quality problems.
MH: This is where a lot of people want to throw up their hands: There are many different definitions of green—saving energy is one, reducing toxicity is another—and in some cases, different definitions leads to opposite approaches.
Lenard: There are always trade-offs. For a kitchen floor, I can choose the Forest Stewardship Council–certified bamboo from China, which is rapidly renewable but used an actual boatload of fossil fuels to get here, or I can choose flooring of local hardwood that is not sustainably harvested.
MH: And which is better?
Lenard: Unfortunately, there’s no way to weigh an extra ton of CO2 in the atmosphere against an extra part per million of formaldehyde in your house against an extra acre of rain forest cut down. You have to choose which issues are most important to you and make design decisions accordingly. Or you can have a contractor make those decisions. There’s nothing wrong with that, but that substitutes the contractor’s preferences for your own.
MH: Let’s see if there are any easy choices. The supermarket asks, “Paper or plastic?” What if your builder asks: Metal or wooden studs?
Harrison: Wood. In particular, wood certified by the Forest Stewardship Council.
Gitt: Using FSC-certified wood may not benefit you as directly as adding insulation in the attic. And it may cost up to five percent more, depending on the product. But it is worth doing: You don’t just save the trees, but you also improve water quality, sustain biodiversity and help reduce the amount of carbon in the atmosphere.
Freed: Instead of two-by-fours at 16 inches on center, go with two-by-sixes at 24 inches on center. If you do that, the building will be easier to build; it will be stronger; and, best of all, you’ll use less lumber. Plus, with the thicker walls, there will be extra room for insulation.
Subscribe to ELLE DECOR magazine
MORE REMODELING GUIDE ARTICLES
