A. The size and spacing of the studs in a treated wood foundation vary with the depth of fill against the foundation walls. An 8-foot foundation wall with 7 feet of fill, for example, will need to resist more weight than one with 4 feet of fill against it.
Depending upon the depth of fill and the soil characteristics, the studs may have to be as large as 2x8s, and the spacing as close as 12 inches. Before attempting a wood foundation you should get Publication A-400, Permanent Wood Foundation, free from the American Plywood Association, P.O. Box 11700, Tacoma, WA 98411. This publication contains...
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