Below-grade waterproofing is an essential component of the entire building envelope. At times, these systems must be extremely complex, for example, at less stable sites employing deep foundations with intense hydrostatic pressure. And water is not the only threat to a structure: Methane gas or contaminated groundwater/vapor may be present on or near the site, a more common scenario due to the fact that more new construction is taking place on ground formerly used for industrial purposes.
