Buckminster Fuller made his Dymaxion houses round because they were aerodynamic and because a circular house encloses more floor area for a given amount of perimeter material. According to the Ottawa Citizen, people are still doing it, for much the same reasons. But instead of aluminum, Laurie Murray and George Kerr built theirs out of cordwood, a very old fashioned form of construction where one takes foot thick slabs of wood laid on their sides.
A foot of wood provides a lot of insulation, so it stays cool in summer and is easy to heat in winter. Steve Linton of round homebuilder Deltec explains the aerodynamics:
The aerodynamic shape of a circular home means air flows around it instead of exerting pressure on flat wall surfaces. That in turn means less infiltration of exterior air than in a conventional home.
Mandala Custom Homes
I am not quite convinced about the argument that a circle is the most efficient way to enclose a floor area; it hard to furnish, as most furniture is rectangular. But they are strong, and Deltec of North Carolina claims that they are hurricane resistant:
In 2005, many of our storm resistant homes were put to the ultimate test when Hurricane Katrina struck the Gulf Coast. None of the Deltec homes in her path suffered any structural damage from Katrina's category 5 hurricane force winds. Two Deltec homes were hit by 20-30 foot tidal surges and winds of over 145 mph and still incurred no structural damage.
Interior, Deltec home
Deltec's motto is "The original green builder" and provides an extensive list of green features and links about green building on their site.
Mandela Custom Homes of Nelson, BC also makes the case for green, and offers a passive house package.
It is unfortunate that so many of them are huge and out in the middle of nowhere, sitting on big green mowed lawns, but if you are in the custom home biz that is the nature of your client and you can't demand that they build less. Now if only the round house movement would meet the tiny house movement.
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