My partner, John Corcoran, will be presenting a paper at this year's Adobe SW Conference in El Rito, New Mexico. John's paper will be on our personal experience of getting through the approval process for an adobe house without insulation on the exterior walls and built on a rubble trench foundation. As outsiders to New Mexico we thought of these traditional practices as integral to building with adobe, and came to adobe building perplexed at seeing new adobes covered entirely with sprayed urethane insulation, wire lath and concrete stucco. Lucky for us and lucky for all New Mexicans, it is legally possible to build a snug warm house in the traditional way. Come to John's talk.
The desire to build an adobe house without additional wall insulation came from both a personal and philsolphical place. We were determined to avoid toxic and non-renewable materials wherever possible. As artists, aesthetic considerations were at the forefront; quite simply, we wanted to build a soulful house made of earth. We wanted to work under the premise of honesty in materials and allow adobe to be adobe: to go beyond its known and quantified properties and to experience what it was to live in a house made of mud.
As knowledgeable builders we did not come to the question of not insulating the walls blindly. We knew of the energy advantages of having R19 in your walls face to face with the only .34 per inch of adobe. But adobe had what is called the effective U-Values which were measured and codified by the Tesuque Thermal Project; great thermal mass. And for me, which was most convincing, was the experiential evidence of the comfort of living in a solar-oriented adobe house with a well-insulated, modern roof. Fortunately, through careful consideration of the house orientation, window placement and size, as well as maximally insulating the roof, we were able to comply with the New Mexico Energy Conservation code and build the house we wanted.
Unfortunately what was most disturbing in this process was a telephone conversation I had with a man who owned a "green" cellulose insulation company here in Santa Fe. Without getting any other details about our house other that that it was adobe and that we were not planning to insulate the exterior walls, he refused to sell us insulation for the roof cavity. He didn't want to discuss or even consider what we were doing. In his mind,we were wrong and he was right. It was rather heart breaking to be thought so ill of especially by someone who was ultimately on the same "side" as us.
As we all wrestle with the question of global warming and our addiction to oil, I think we must rely on our own instinctual and experiential knowledge as much as in scientific and technical information. For us, building small and living simply was equal part in our decision making. To live in a small house, we knew it had to be beautiful and sparse and that, for instance, though a fireplace might not be considered "energy efficient," for us it would be our winter heart: a place to gather, to read, share a evening meal or play a game. In essence what I am trying to address here is the importance of knowing yourself and family when building a home, and as great as Hers and Leeds are for our commercial and developer-built buildings, they may not be the right bench mark for us as individuals.
Incidentally our south,west and east walls are laid at the 14 inch direction with another 2 " of plaster while our north walls are double 10" walls with a 2" airspace with 2" of plaster, and our roof is insulated to R 40.
For more on rubble trench foundation.www.buildnaturally.com/EDucate/Articles/RubbleTrench.htm