Editor’s Note: This is the first of three articles on practical, cost-effective, green building techniques. To read the next article in the series, click here .
A recent study points out that builders overestimate the cost of building green by over 300 percent.
They tell clients that their new, green home will cost 17 percent more than a traditional one—when the actual increase is closer to 5 percent.
This is understandable. Doesn’t it sometimes seem as though we only hear about how much more it’s going to cost to build homes that offer higher indoor air quality, don’t deplete natural resources or contribute to greenhouse gases?
Architect Gwynne Pugh of Pugh + Scarpa Architects believes that the vast majority of green practices cost no more than traditional ones, and it’s the last “extreme green” 15 percent that pile on cost. “It’s actually less expensive to use the sun’s rays to heat water than produce electricity through photovoltaics, but which one is sexier?”
Listed below are our first five picks for lower cost, green building techniques.
1. Reduce the Use of Framing Lumber
At 16 inches on center, most houses are over-engineered. Increase on-center spacing to 19.2 inches or 24 inches—and follow a few other Advanced Framing Technique (AFT) ideas and the savings can be substantial. Strategic reductions in framing lumber save money and leave more room for insulation. AFT, developed decades ago by the Forest Products Laboratory and the National Association of Home Builders*, is a proven way to use less lumber, yet many builders don’t follow its tenets.
Dimensional design is another waste-reducing measure—building to the common 24-inch sheet stock module generates far less job waste. Engineered lumber like Glulam beams and I-joists offer higher quality, strength and dimensional stability than solid sawn lumber. Aligning floor, wall and roof framing members directly in line—distributing loads evenly—allows the use of one top plate rather than two. Creating two-stud corners and eliminating horizontal blocking are other AFT innovations.
According to the Department of Energy’s Office of Energy Efficiency and Renewable Energy, fully implementing advanced framing techniques can result in materials cost savings of about $1,000 for a 2,400-square foot house and labor cost savings of between 3 and 5 percent, not to mention annual heating and cooling cost savings of up to 5 percent because of better insulated walls.
2. Recycle Job Waste
Up to 30 percent of the solid waste in landfills is construction and demolition debris, and it’s getting more expensive to dump it there. A growing number of states are mandating reduction in landfill consumption (50 percent by 2008 in California) and putting teeth in their measures by raising fees. Those costs aren’t coming down, and that makes jobsite recycling an important area of focus for builders looking to cut costs.
There are three ways to approach jobsite recycling: on-site separation of materials, construction-phase-based pickup and commingling for later processing at a recovery facility. A growing number of recycling-specific hauling companies are available, like Clean It Up Mark! in Portland OR. Founder Mark MacGregor claims builders can save up from 15 percent to 25 percent in disposal costs.
MacGregor charges a per-square-foot-fee: about $900 for a 2,000-square foot house. He estimates that for the same house, traditional haulers would charge about $1,200, based on a $350 to $400 base fee, plus a tonnage overage. That might take three or four dumpsters full, at $350 or $400 base fee, plus an overage on the tonnage—$1,200 is not an unreasonable assumption.
In a 1993 study for Metro, the Portland municipality, MacGregor found that in a 3,500-square foot house, wood accounted for 65 percent of the waste, drywall for 23 percent, cardboard for 3 percent and metal for 1 percent. “This year, we’ll achieve near 100 percent recycling of C & D waste,” says MacGregor.
3. Recycle a Factory Building
The most sustainable form of building is adapting one that exists
