He Built a Home of Sawdust/Concrete
(Page 3 of 4)
January/February 1978
by O. A. Fitzgerald
To test the sawdust-concrete, Friberg cast slabs 32 by 48 inches square and one inch thick. Close to the edge of these slabs he drove eight-penny nails and drilled rows of holes with a power drill. There was no splitting. Then he sawed off strips an inch wide with a power saw. With a power sander he produced a smooth surface that could be painted. He tested the slab for insulating value and found it equal to a foot or more of concrete.
RELATED CONTENT
Friberg believes that a 3-5/8 by 32 by 48-inch slab, which can be precast and cured during spare time, will be useful in farm buildings. This size will span two studs or floor joists or can be sawed to fit between studs. Northwest farmers already are showing interest in its use for dairy barns and poultry houses, where the need is great for a low-cost material that has high insulating value.
Someday a method of waterproofing the concrete may be found. Until then Friberg recommends that it be used indoors only. It has another limitation also. With a load strength only one-quarter to one-third that of ordinary concrete, it can't be used in sidewalks or driveways or for floors and walls that carry heavy loads.
But even if these limitations are never completely overcome, Friberg sees a tremendous field for the tiny diatom and the sawdust and shavings piles. His living room floor, for example, is a solid block of the low-cost material. Carpet and linoleum are fastened directly to it. The roof also is a solid block, covered with roofing paper and pulverized pumice stone. In the walls of his house the main load is carried by a layer of regular concrete bricks. Double-thickness sawdust-concrete bricks provide the insulation.
Since diatomaceous earth deposits were investigated during the war, state departments of geology and schools of mines have information on their locations. So, if the prospective builder can locate a convenient pile of pine, larch, or fir sawdust and shavings, and it isn't too far from a deposit of diatomaceous earth, Friberg has found a way for him to bring them together to produce a new type of low-cost building material. a
THE FRIBERG HOUSE 30 YEARS LATER
Recently, MOTHER staffers Martin Fox and Travis Brock trekked to Moscow, Idaho to locate the wood-fiber/diatomite/concrete home that Popular Mechanics reported on 30 years ago (see preceding story). Our intrepid staffers wanted to find out: Was the original building still standing? Had the concrete mixture settled, cracked, or disintegrated? How had the structure weathered thirty years of cold Idaho winters?
The answers to these questions—Martin and Travis quickly learned—were "yes", "no", and "very nicely, thank you".
