"For many of our families, utility payments cost as much as the mortgage," says Kevin Campbell, project coordinator with the Habitat for Humanity (HFH) chapter in Lynchburg, Virginia. "If you can cut such a big portion of the monthly costs, it's hard to overlook it."
Since Habitat's primary goal is providing affordable housing, energy efficiency seems like a natural fit. The chapter's "Earthwise House" showcased both energy efficiency and environmentally sensitive construction. Here are highlights from the energy package.
To look at the house, you'd have trouble noticing any difference from the typical Habitat project in Lynchburg. The rectangular shape and the simple floor plan stress function and affordability. Early on, the designers decided to use the same overall design that volunteers had built many times before.
"It didn't take any longer to build the Earthwise House and it wasn't a bit harder," says Kevin.
Even without changing the floor plan, they were able to take advantage of solar heat. They simply found a site with good solar exposure and positioned the house so its long side faced south. A few windows were moved to the south side, even though the overall glazed area was unchanged. Full length glazing was added to the back door in the kitchen's south wall. This "sun-tempered" approach grabs free heat without adding to construction costs.
Orienting the house toward the sun also allowed a solar water heater. General contractor, Al Maddox, collected used solar panels and added a heat exchanger connected to the home's water heater tank. The circulation pump is powered by a small photovoltaic (solar electric) panel.
Cellulose insulation was used throughout the building. Being made from recycled newspapers gives it "green" credentials. They used the wet spray method to blow cellulose into open wall cavities. Because it's blown in, cellulose fills the cavities better than the average job done with fiberglass batts. That eliminates voids and blocks air leaks that can increase heat loss.
Insul-Tray panels stapled to the bottom of the floor joists allowed cellulose to be blown into the floor, too. By filling the cavity created by the 2x10 floor joists, they reached R- 38. They ran short on the donated Insul-Tray panels and had to finish the job by stapling housewrap to the floor. Unfortunately, the weight of the cellulose popped the staples, so wood lath had to be nailed under the joists. This provided a clear lesson on the advantages of using the Insul-Trays, which were designed for that purpose.
One job often assigned to the home owner is caulking around wall plates, windows as well as electrical and plumbing penetrations.
The foundation is one component that Kevin is reluctant to turn over to volunteers. He hires skilled masons for block jobs and concrete subs for poured ones. However, this time he used Faswall insulated concrete forms. Once the footing was complete, volunteers found it easy to stack the lightweight foam blocks. They added some rebar and called the concrete truck. (It will be a pumper next time!) Although the insulated forms cost more than conventional forms, volunteer labor brought the total cost in about the same as hiring a sub.
This Earthwise House was an experiment, encouraged largely by major a donation of materials from Louisiana Pacific. Most of the emphasis was on building materials with recycled content, such as drywall, carpet, nails and cellulose insulation. Other materials, such as oriented strand board and finger jointed studs, make good use of forest resources. Paint free of volatile organic compounds (VOCs) helped protect air quality.
"We've used bits and pieces in other projects," says Kevin. All the houses have cellulose in attics. Six have carpet from recycled pop bottles. Fifteen have solar water heaters, some of which preceded the Earthwise project.
"The earth-friendly materials are definitely more expensive and many of them can't be bought locally," says Kevin. "We have to do what we can."
For more information about Lynchburg's Earthwise House, call 804-528-3774.
Habitat for Humanity
HFH is a nationwide home building organization. By using volunteer labor and it's own financing, HFH promotes home ownership for people with limited financial resources. If it were a single business, Habitat would rank as the nation's 17th largest builder. Instead it's an umbrella group for more than 1,000 local chapters around the U.S. and in other countries. For the most part, local chapters support their own projects. Most run entirely on volunteer labor. Others, like Lynchburg, have a small paid staff. Occasionally, the national office collects major donations, such as hundreds of compact fluorescent lamps, that it directs to local chapters. HFH even has a Department of the Environment at the national level. For more information about Habitat for Humanity call 800-HABITAT.
This article appeared in Energy Source Builder #34 August 1994