Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SATURDAY, January 22, 1994 TAG: 9401220114
SECTION: VIRGINIA PAGE: C1 EDITION: METRO
SOURCE: RENEE SHAFER STAFF WRITER
DATELINE: LENGTH: Long
Orr's house cuts into a hillside on High Street in Salem. Sliding glass doors make up his south and west walls, capturing all the sunlight he needs to warm his house. "The ground temperature keeps the house at 50 degrees year-round," Orr said. "All I have to do is supply 22 degrees of heat."
Orr, a retired case manager for the Department of Veterans Affairs in Salisbury, N.C., moved into his dream home with his wife, Marianne, in July. The house, which he designed, took him two years to build.
He first read about alternative heating methods 20 years ago and has been collecting articles and books since. "We have a heat source that rises every morning," Orr said, pointing to the sun. "We just don't use it."
Glass doors provide passive solar energy. The sunlight pours into the house, creating an airy environment and warming the rooms during the day. The heat is absorbed by the slate floor and released at night.
In the summer, when the sun rises higher in the sky, a long overhang on the southern exposure keeps the house shaded. Though the Orrs found their first summer a little hard to bear, they have since finished insulating the house and are expecting it to be more comfortable this summer.
The system Orr uses is a combination "hybrid solar" and "earth tempering" system, explained Robert Schubert, dean of research in the College of Architecture at Virginia Tech.
A hybrid solar system combines both active and passive systems. Active systems collect and store heat. They rely on mechanical assistance to transport the heat, such as the fans that Orr uses throughout the house, Schubert said.
Passive systems simply collect heat without transportation or storage, relying on the natural flow of energy. Passive heat warms Orr's home as glass doors catch direct sunlight between 9 a.m. and 3:30 p.m. When the day is overcast, Orr relies on his kerosene stove.
Orr has 13 glass doors throughout his house. He bought them second-hand for between $20 and $50. The two fans he uses to distribute the heat cost him $50 each.
Earth tempering is the use of the earth as a medium to prevent heat loss by air movement. "His house is not set deep enough in the ground to get a lot of ground heat," Schubert said, "but he's minimized the amount of exposed surface where heat can be lost or carried away by the wind."
The main benefit of Orr's design is the amount of insulation that the hillside and other synthetic materials provide.
"We used eight to ten inches of concrete to hold the dirt back," said Harold Keene, Orr's carpenter. "Then we sprayed it with five to six inches of polyurethane foam to insulate it and coated that with tar to seal it. There's three-quarter-inch Styrofoam insulation against the inside of the wall, and then that's covered with plaster."
By using a combination of Styrofoam and polyurethane with the thickness he described, Orr's house has approximately double the insulation of a normal house using fiberglass insulation, said Gary Spates, sales supervisor of Washington Gas and Energy Conservations Systems, a company that handles thermal insulation.
Another benefit in using these materials is that they are not combustible. The concrete itself is fireproof. Although neither the Styrofoam nor the polyurethane foam is combustible, both can give off dangerous gases if not properly used with a fire-rated material, said Skip Nininger, Salem's building inspector.
"I wouldn't call the house totally fireproof," Nininger said. "It has oak wood fixtures and other furnishings inside."
Bob Savage, president of Virginia Solar Co., estimates that there are about 50,000 solar heating systems in the state today. "Solar heating will only provide you with 50 percent of your heating," Savage said. "Beyond that, the equipment is just too expensive. You need back-up heating like heat pumps, gas, oil or wood in addition to your solar heating."
Schubert said the motivating force for alternative heating today is largely environmental, but believes there are economic benefits as well. "They are expensive systems, but a good design should be able to collect and store enough energy that it pays off its costs within seven years. The economics is not in the initial cost."
Adding passive solar systems such as a greenhouse to an existing house raises the value of the house, Schubert says. "You increase your square footage, add a warm space to your home for the winter, and if properly ventilated, a light and airy place for the summer."
Before adding a solar addition to your house, Schubert warns, make sure the building is efficient to start with.
If you are considering supplementing your heating with solar energy, Apco will provide you with an estimate of what your savings may be.
For more information on alternative heating equipment, Real Good, a California company, offers a free catalog of mail-order equipment, product information and technical services. The telephone number is (800) 762-7325.
by CNB