Saturday, February 2, 2008

The greening of suburbia

All right, this article in the Washington Post on "Can Big Be Green?" has gotten me all riled up. The premise is that even oversized new houses can be more "green" than small old houses. Basically, the article gives high-end developers and their clients the opportunity to justify building McMansions by insisting that even though they consume more land, raw materials, and energy than smaller/older dwellings, it's OK! Because they're sprayed with impermeable insulation and virtually draft-proof! So you can have six bathrooms and not feel guilty, or even have to worry about your heating bill!

The article defines "green" as follows:

"Generally speaking, a house is called green if it uses energy, water and natural resources wisely and offers good indoor air quality. "

What the article does not mention is that oftentimes, particularly in a couple of the neighborhoods specifically mentioned (Somerset, Chevy Chase DC), the only way to build a new house is to tear down an old one. Oftentimes that old one is a perfectly good and serviceable house, maybe a bit small or needs work, but probably has potential.

I need someone to explain to me how bulldozing such a house (which might contain excellent-quality old-growth wood and other natural materials) and throwing it in a landfill, then tearing out all the remaining trees in the yard so a builder can come in and construct a large, towering new house as far out to the property line as possible, using particleboard and Tyvek and pressure-treated lumber and vinyl, is being "green." How is that a wise use of energy, water, or natural resources?

At the very least, this is a colossal waste of resources, even if the old house was not particularly energy-efficient. It's also replacing natural materials almost entirely with chemical-infused manufactured ones, which may or may not be healthy to live in (time will tell). Finally, such an immense infill house inevitably has negative physical, aesthetic, and fiscal ramifications on an established neighborhood, although that's a rant I'll save for another day.

Even if the new superdwelling is built in a vacant area and no old houses were hurt in the filming of this eco-movie, its big footprint is occupying land which once absorbed rain, thus decreasing permeable soil and causing more runoff into area waterways (or neighboring properties). Since most new houses usually have a good-sized paved driveway and/or parking area for the three-car garage, the permeable surface is even further reduced. In terms of reducing runoff and pollution of our waterways, it would be more green to reuse and expand an existing building footprint than to create a new one.

Call me crazy, but I don't understand why anyone would want to live in a Thermos-like dwelling. Old houses may have drafts, but this also serves as a passive ventilation system. Houses built before the advent of air conditioning and modern climate control often have built-in design features to maximize winter heat retention and summer cooling. Air circulation through the exterior envelope, and cross-ventilation through the room arrangement, was a given. These features cost nothing to use, and have worked well since humans first lived in a built environment. If your new house is completely draft-proof, how exactly do you plan to get fresh air circulating through it? Why, an HVAC system! Which requires materials to build and energy to run! Maybe your air quality inside will be good, but is it truly fresh?

The article does not mention that the reason we have black mold, and black mold lawsuits, is precisely because new houses these days are built to be so airtight. Wrapped in Tyvek and vinyl siding, or slathered with synthetic stucco, and sealed with vinyl thermal windows, they don't have the passive air circulation of an older frame or masonry house with wood windows. Houses need to breathe and exchange air, particularly since they are exposed to varying levels of moisture from the inside and outside. When moisture gets into a wall and cannot escape, you get mold. What happens when the wood used to build a house is waterlogged by rain or insufficient curing/drying before the Tyvek and the spray-on insulation goes on? How will it dry out if your exterior walls are sealed like a Thermos? Ever smell a moldy Thermos you forgot to empty and wash for awhile?

So basically, I think it's great if you are going to build yourself a McMansion no matter what and you decide to jump on the "green/sustainable" bandwagon and stick a few solar panels on top. But it would be even greater if realtors, developers, builders, suppliers, consumers, shelter magazines, home-improvement TV shows, and Ty Pennington would recognize the value and potential of reusing existing buildings rather than putting up new ones. Sustainability, like preservation, is about long-term value and stewardship over generations, not the "I want it all and I want it now and I'll throw it away when I'm done with it" culture we live in these days.

This would be a more balanced article if the author had talked to some preservationists, instead of just the National Homebuilders and the LEED people. And it's crystal-clear to many of us in the historic preservation field that national environmental policy needs some help. My friend Richard in DC blogged about this a few days ago and has some additional salient points.

1 comment:

Karen said...

Save us from Green