Monday, January 5, 2009

“Demand Dims for Energy-Efficient Homes”

“As fuel prices fall, buyers reluctant to pay for green extras”

This title and sub-title are direct from a Friday, January 2nd Philadelphia Inquirer article. Upon reading the article, I discovered –to no surprise, that it was the higher cost of add-ons, such as solar panels and other “eco-friendly enhancements,” which had reduced demand. In essence, prospective buyers just don’t want to pay the associated increased first cost, according to the article, especially in these more challenged economic times.

The eco-friendly enhancements listed, aside from solar panels, were dual-pane windows, high-performing insulation and low-leakage ductwork. Reading this list, you might think that typically, single-pane windows, low to non-performing insulation and high-leakage ductwork are installed in a conventional home. I say this in jest of course, but still, it makes one wonder.

Just say no to add-ons –for now

Energy-efficiency doesn’t start with add-ons though. And you can build an energy-efficient home with conventional-performing insulation, like fiberglass batts, (and believe it or not, even single-pane windows). The key is first eliminating all air leakage through the building envelope (walls, floor and roof). This requires properly installed insulation –whether batt or spray-foam, sealing at various joints and junctures –like wall to roof and around window and door rough openings, to name a few methods. Second is to ensure a high/recommended R-value –and make sure you have eliminated thermal conductivity at studs (studs have a) low R-value to begin with and b) cold/hot air is easily transmitted through a stud into a building, it’s basic physics; click here for an excellent white paper/primer on thermal bridging). This is actually simple, and can easily be accomplished by installing 3/4-inch thick rigid insulation over top the exterior wall sheathing. Once you have a tight envelope, you have a more efficient heating and cooling system by default, simply because without air leakage, it will need to work less hard to keep the occupants comfortable. Working less hard means less money in utilities.

Making cents

Do these two measures require a bit more work on the part of the sub-contractor? Yes. Does a tighter building envelope require a ventilation system for proper air exchange? Yes. But I also believe these measures can be easily implemented by any homebuilder without having to change the basic design of the house, and with very little cost increase when compared to more costly add-ons. And taking into account that most homebuilders have each home down to a science, i.e.: they know the design, the material list, the sub-contractors, the profit and etc., I think this first step makes some green cents, for the homebuilder as well as the occupant.

Of course, I’d like to see homebuilders move far beyond these simple measures. In fact, I believe it’s imperative (check out the 100k house as a great example of energy/resource efficiency on a low budget). But it’s a start, and sometimes, even I’ll admit that baby steps can sometimes lead to giant leaps faster than we think. We also need to focus way more attention on our existing residential housing stock, making it more energy and resource efficient. Without that, we’ll have hardly made a dent (and on that front, click here for an e-book on my house –a circa 1920 brick twin, to see what I'm doing to increase its efficiency).

image is of thames & kosmos power house, a toy for ages 12+

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