Page 94 - Construction Waterproofing Handbook
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BELOW-GRADE WATERPROOFING 2.57
FIGURE 2.72 Transition detailing for sheet membranes. (Courtesy of Grace Construction Products)
including toothpaste. Typically, bentonite waterproofing systems contain 85–90 percent
of montmorillonite clay and a maximum of 15 percent natural sediments such as
volcanic ash.
After being installed in a dry state, clay, when subjected to water, swells and becomes
impervious to water. This natural swelling is caused by its molecular structural form of
TABLE 2.7 Material Properties of Hot-Applied Sheet Systems
Advantages Disadvantages
Material costs Safety
Similar to builtup roofing Difficult vertical installations
Some installations are self-healing Poor elastomeric properties
