ODYSSEY PART 21 - I: How a solar house is born – Part I

Q. You designed and built your solar home at High Wind back in the mid-1980s. Can you tell us how that project was developed, both from a technological and philosophical standpoint?

A. Back then, Hawthorne House was pretty much state-of-the-art. A great deal of research has gone on since that period when people were just beginning to learn about “alternative energy,” including building with a passive solar design. (“Passive solar” means no machines or active panels at work – just giving the sun maximum opportunity to shine in.) I’ll detail our thinking process and how the construction unfolded, and then will touch on what’s come over the horizon more recently.

A primary purpose for establishing the High Wind Association and community in 1977 was to create demonstrations of energy efficient buildings that expressed our concern for preserving and enhancing the environment, and then to bring people in to educate around ecological sensitivity and sustainability in all facets of life.

It wasn’t until 1985 that my husband Bel and I could consider building our own home at High Wind, which would join our flagship bioshelter and (eventually) other private dwellings on a high ridge southwest of Plymouth.

Our geography presents interesting challenges. Its 43 degrees latitude makes for winter temperatures that can drop to minus 20 below zero and soar to 100 degrees in summer (though neither extreme is prevalent). Our exposed, high elevation is subject to frequent strong wind velocities. And because our hill slopes east rather than south, it is not considered ideal for solar construction. These factors were key in designing a home that had to work in tandem with nature. Actually, Bel and I came to sit on this hill for years before High Wind began, connecting to this spot of earth and its incumbent natural dwellers. We spent a lot of time examining the natural contours of the site, noting when and where the wind blew, where the snow fell and collected, and how the sun moved (such as seeing what time it disappeared over the west hill on the shortest day of the year). In fact, patterns of light, weather and views (and integrating these with projected social functions for spaces) became the pivotal guiding factors as I began to sketch plans.

Now, when we were ready to build, we had to take into account these and other factors – in a very practical way. I pored over hundreds of articles, books and pictures, researching both design possibilities and the newest technological developments. Our architectural bible became Christopher Alexander’s A Pattern Language. For Alexander, building becomes poetry – not simply a matter of bricks and mortar. As we proceeded, we began to see our own house unfolding as a partner in a distinctly artistic enterprise with its own personality of grace and beauty and power. We named it Hawthorne House because each spring the hedgerow of tangled wild hawthorne trees on our east flank becomes a cloud of white blossoms.

Many drawings later, we invited in a good friend from Spring Green, Keith Symon, who was not an architect but a fine carpenter/cabinet maker who had designed and built a house we liked, who knew a lot about passive solar, and whose ecological and aesthetic integrity we trusted. It was particularly important to me to prove that a technologically efficient solar house could also be artistically compelling; I wanted it to be lyrical, to “knock your sox off,” and at the same time to be understated, warm and inviting. Together, we talked and dreamed and drew; then we modified the more fanciful ideas and scaled down the dimensions to reasonable proportions. In spring 1985 we discovered Peter Paiser, a builder of earth-sheltered homes from Two Rivers who was intrigued at the idea of combining his technologies with others, including passive solar. Between Bel and me, and our designer and builder, we came together on the “final” plan – though we kept it fluid and actually made changes throughout construction.

In order to be part of the constant decision-making and to eyeball the results, I was on-site most of the time serving as general contractor – running for supplies and lining up subcontractors. Correspondence between Keith and me continued briskly since his guidance and overall vision were critical in making everything work together. Often we were in virgin territory, and Pete, on his end, was ingenious at knowing how to resolve complicated construction puzzles or errors with remarkable creativity and speed. Keith appreciated especially that Bel and I were intimately involved with every step of the project; he would not have taken on the assignment if we had tried to turn over the entire responsibility to him and Pete – to be handed the key at the finish.

The bulldozer rolled in to excavate Aug. 1, 1985. Soon the site resembled an archeological dig, with the different levels of earth connected by ladders, and a fascinating geological history was spread out in the open cross sections. The glacial residue, or moraine, consisted of topsoil, clay, packed round stones, fine pebbles, and beach sand, with the course of a long-ago stream clearly visible. Pete and his crew of one or two apprentices did most of the construction over the next 10 months. (Our son Eric also came to help for a while). I found masons to artistically cut and lay the slate floors and to build the fieldstone hearth (we collected glacial rocks from our own land). We also arranged for other floorings and the active solar hot water system (designed and assembled by a plumbing teacher from a technical college). As snow piled up around me in the partially enclosed building, I sealed the boards for the exterior cedar siding just ahead of the carpenters nailing them on.

I had contacted makers of innovative, energy efficient products all over the country, from low-flush toilets to air-to-air heat exchangers. Because the house would be open indefinitely as a public demonstration, we received a number of substantial discounts and outright donations (including all our water-saving faucets from the nearby Kohler Co.).

The house, being next to a hardwood forest that protects it on the north, is dug into the west hill so that roughly half the building is underground, sheltered from the prevailing winter west winds. The other half of the house is passive solar, exposed to capture the sun and sweeping views over the valley to the east and south. From the beginning, the architecture was dictated by the land, with the house growing organically out of the existing earth contours and giving a feeling of stepping down with the hill. The interior spaces evolved out of this natural flow and from light patterns from the huge triple-glazed windows.

Here, in brief, are the (abbreviated) nuts and bolts describing some of the design specifics and energy features:

House plan: It’s 1½ stories and roughly 2,300 square feet. It’s “stick-built,” double stud construction with poured concrete foundation and berming walls. A sun deck and herb-rock garden are accessed from the dining area on the south. A north-facing screen porch is a cool oasis in summer with views into the woods and over the valley. The primary energy-saving elements in the house are triple-glazed windows, superinsulation, earth-berming, and mass for heat storage.

Upper level: Living room, dining/kitchen area and sunspace/study on the upper level are open-plan to facilitate radiant woodstove heating. The master bedroom and bath are also on this floor. Ceilings vary from a cozy 7 to 8 feet when stepping down into the living room. There’s a modest cathedral (11 feet) sloping up to clerestory windows over the kitchen to light the darker areas to the north. (You don’t want to lose too much heat in a high plenum.)

Lower level (walk-out): A large study, two guest bedrooms, bath, and utility room.

Floors: Where the house is built directly on-grade, there is 4 inches of poured concrete, under ¾-inch slate. Where not on-grade, there is maple or vinyl flooring.

Walls: On the north, west, and east they are 12 inches thick with insulating values of R-56; south walls are R-45 and 6 inches thick. Sprayed urethane (5½ inches) insulates the 12-inch walls; 2-by-4 stud walls have fiberglass insulation.

Roof: Trusses are 18 inches deep with blown-in cellulose for a protective R-60. Asphalt shingles are lapped more tightly than normal to protect the (19) low pitches (ranging from 2½ inches to 12 inches to 6 inches to 12 inches). Roofs on a solar house usually have a 24-inch overhang to keep out a maximum amount of summer sun, but Keith felt we needed every bit of winter sun we could get and it was worth the small inconvenience of a little less summer protection – so our overhangs are 18 inches.

Windows: The key element in our passive solar scheme is letting the sun in directly and retaining its heat as long as possible. Though our degree-days in Wisconsin are 7,000, we do surprisingly well, since the coldest winter days are often sunny. We opted for an abundance of south-facing windows as well as a number on the east to catch morning sun. By opening the fairly small living room with huge windows and setting them 22 inches from the floor, the outdoors becomes an integral part of the room, keeping us in touch with the wild meadow surrounding the house.

All vertical windows are Hurd Heat Mirror, produced in Wisconsin: there are two layers of glass separated by a 1-inch air space, sandwiched with an invisible 2-mil-thick reflective film in the middle. The windows have the “magical” ability to allow direct solar gain into the house by day in winter, but keep 85 percent of radiant heat from escaping back out at night. Conversely, in summer the windows allow in light but keep much of the long wavelengths of heat on the hotter outside of the glass.

Eventually some of the windows failed and their replacements had the newer feature of argon and krypton gas injected between the glass layers. There are two Velux skylights to bring light into strategic spots along with several high clerestory windows.