Traditional ways of designing houses are no older in the United States than in New England. Indeed, traditions die hard. Colonial-style homes are still being built amid the undercurrent of modern solar projects.
How can you blend the best of both worlds?
One of the most creative syntheses of colonial and solar designs is that of Doug Bowen and Ken Moller of Hancock, N.H. The north, entrance side is built with the traditional old-time style of small, sparse windows set against clapboards. The south, back side, however, is designed almost entirely with a glass solarium as part of the envelope double-wall concept.
What ties the two spheres together like a perfect equation is incorporating both styles into a gambrel structure.
Better than any other familiar style, the gambrel shape (a roof having two slopes on each side) accommodates the circle of the envelope that encapsulates the living space.
A double insulating wall across the breadth of the roof and north side of the house moves warm air trapped by the sun in the solarium.
The air rises naturally to the top of the south-side solarium, then inside the 12-inch double wall, across the roof, down the north side, under the basement, and back to the solarium to complete and continue the cycle.
An attractive example of this imaginative synthesis is the home that Mr. Bowen built for Bill and Nancy Hallberg in Sharon, N.H.
The 3,200-square-foot, three-story house appears from the street side as an elegant version of an old-style home that is appropriate to traditional New England. The 750 square feet of glass on the backyard side thrusts the design into the 1980s.
The Hallbergs have lived through their first winter in the house, and are pleased that the envelope reduced their backup heating (wood and electricity) to the equivalent of three cords of wood. This is probably a quarter of what would otherwise be needed for such a large house if it were designed entirely in the old style.
The Hallbergs said they probably had a fire a week in extreme conditions, just to take the chill off.
As opposed to the traditional house that has the outside temperature and the inside temperature, ''this has the outside temperature, the solarium temperature , and the inside temperature,'' says Bill Hallberg. ''It's coldest here about 5 in the morning. It could be 20 degrees below zero outside, maybe 40 above in the solarium, and 70 degrees in the living space.''
In less-severe weather, the buffer zone of the solarium turns much warmer -- at times reaching 80 degrees.
About 38 square feet of nonliving space on each floor is needed for the north-side, double wall as part of the system. The Hallbergs figure that the solarium more than compensates for taking the space used to wrap the living area.
The solarium offers them not only space heating, but also a sunny place to grow vegetables and flowers in the winter, a sunny spot to relax and read a magazine, a sense of openness from the expanse of double-glazed glass, a place for children to play, and more natural light throughout much of the rest of the house.
In summer, when the sun is high overhead, an overhang is designed so that no direct heat pours into the kitchen and living room. Vents in the roof are opened and fans blow out any heated air that rises from the solarium.
In winter, the vents are closed and fans help push the warm air through the buffer zone and down the north side.
Designer and builder Bowen is convinced that the multiple benefits of the envelope concept make it more appealing and useful than merely a black-wall solar collector outside. When the envelope is combined with indigenous styling, the attraction increases.
''If you can also grow vegetables and sit inside the collector,'' he says, ''plus if you can incorporate hot water into it, then you can get four commodities for the one system.''
The Hallbergs add a fifth: ''As far as we're concerned, we wanted a house that reflected us. And No. 2, we like running money to the bank that OPEC, or somebody else, would be getting every month.''