 hen we launched our business in 1975, our goal was to design comfortable homes using renewable natural resources. We began by designing the traditional style passive solar homes of the day. At that same time we discovered the work of Christopher Alexander and realized that his approach to designing comfortable homes fit beautifully with our own developing design style.
Technology came into the mix as well, and we marveled at the advances in materials technologies, then available, and how reluctant the home building industry was to adopt them!
SUPER INSULATION EXPANDS DESIGN OPTIONS
 The conventional approach to designing a solar home, even today, is illustrated in the diagram on the right. First, the heat loss is calculated for the type and size of the structure. Then the amount of south facing glass is determined for the desired solar gain. The thermal mass is then sized in proportion to the solar gain.
Somewhere along the way, we realized that the pivotal element in a solar home is a well- insulated exterior shell. Using super insulation, high performance windows and careful construction methods, the structure could be built much tighter with less infiltration.
 If we could cut heat loss in half by increasing insulation and decreasing infiltration, the relationship between solar gain to floor area would change, which would then change the amount of thermal mass.
We found the super insulated building system we were seeking when we discovered polyurethane filled structural insulated panels.
Many benefits came from this advancement. Using a super insulated shell allowed us new design freedom! Gone were the mandatory clerestory windows, trombe walls and banks of floor-to-ceiling south glass. Gone was the bermed, windowless north side of the home that couldn't help but be ugly. We could now design conventional-looking homes in any architectural style—ranch, Victorian, contemporary, country farmhouse, Japanese, Southwestern, mountain cabin. You name it! We could now place windows where they would be most useful and attractive without impacting the overall efficiency of the home. There was a cost benefit too, since the floor to ceiling south windows and the extra thermal mass were expensive. Super insulated structures cost more to build initially than standard homes, but our new generation homes were simpler to build, more cost effective, more comfortable and much more aesthetically pleasing.
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