A. Bill Palmer, former editor of Concrete Construction and president of Complete Construction Consultants in Lyons, Colo., responds: In general, concrete and masonry foundations need to be either dampproofed or waterproofed, depending on the soil conditions. Section R406.2 of the 2006 IRC requires waterproofing "in areas where a high water table or other severe soil-water conditions are known to exist" and defines several different acceptable waterproofing methods. But even normal soils contain a certain amount of water vapor, which can move through masonry and concrete, so section R406.1 requires acceptable dampproofing treatment even when walls don't need waterproofing. Most people use a black bituminous coating.
The same provisions apply to precast foundation walls — though that may change. Under conditions where waterproofing is required, precast walls need the same waterproofing treatment as cast-in-place concrete and concrete block foundations. But Greg Stutz, vice president of technical services at the National Precast Concrete Association, says the...
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