First-- although I really like the idea of the uphill patio garden/greenhouse (I would add a nice, wood-fired hot-tub), it seems to me that one of the main reasons to build on a slope is to catch some nice passive-solar gain by building on the sunward side.
Now, his home site is in far Northern Idaho, and he has plenty of wood on his land to burn, so I can forgive him the fact that he seems to need to make extensive use of a wood-burning stove for supplemental heat. However, the holy-grail of earth-sheltered housing is to design it in such a way that it rarely, if ever, needs supplemental heating or cooling.
The closest he comes to allowing for some southern exposure for passive solar gain are the clerestories and gabled roof modifications. I could see a "stairstep" clerestory design working very well for this, keeping the overall slope of the roof going down-hill, alternating between slightly sloped roof and steeply sloped windows. This would also reduce the depth of the eaves we would need to shade in summer, because each line of clerestory windows would be short.
Otherwise, if we release our attachment to the simple shed roof, then we're relieved of the either/or decision of sloping the roof with or against the hillside's natural slope. Instead of a complex gable, why no just build the entire home as a vaulted roof, with north end of the vault abutting the uphill patio, and the southern end glazed? Use impervious membranes over the vault roof and well beyond the walls/foundation to shed water to the sides, rather than to the front of the house. The sides of the house, then, would be below-grade, taking advantage of the temperature moderation. The floor and walls would act as passive heat storage from the sunlight penetration in Winter, and the Summer sun can be shaded by a an overhanging roof. We can even consider building multiple vaults side-by-side in such a way as to create more space for a single dwelling, or create multi-unit dwellings that are connected (like his offset rooms).
"Perfect" southern exposures should be saved for Zone 1 gardens in the north, and are too much heat exposure in the south.
Just my opinion--I thought it was odd at first, going that far against conventional wisdom.
"You must be the change you want to see in the world." "First they ignore you, then they laugh at you, then they fight you, then you win." --Mahatma Gandhi
"Preach the Gospel always, and if necessary, use words." --Francis of Assisi.
"Family farms work when the whole family works the farm." -- Adam Klaus
I have lived in a modern, well-insulated home that was designed with passive solar in mind in Central Wisconsin. It still needed supplemental heating in Winter. Although it's not Zone 1, it was still a good idea there.
I believe we can do better than this. With proper design, I think we can make a HVAC (or at least H_AC)- free building in just about any climate.
Kevin EarthSoul (real, legal name)
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