Page 426 - Construction Waterproofing Handbook

10.28 CHAPTER TEN

FIGURE 10.28 Pressure relief piping and sump system to reduce hydrostatic pressure on envelope.
(Courtesy of Anti-Hydro International, Inc.)
and algae. Where applicable, deck drains, roof drains, gutters, and downspouts should be
installed to gather collected water and disperse it without subjecting above- and below-
grade areas to this water. Figure 10.28 details the use of pressure relief piping and a sump
pump system to reduce hydrostatic pressure when site drainage is inadequate.

ENVELOPE REVIEW

Successful building envelopes include most if not all of the following features:
● Few protrusions and penetrations on exposed envelope portions
● Minimal number of different cladding and waterproofing systems to limit termination
and transition detailing and trades involved
● Minimal reliance on sealant systems for termination and transition detailing
● Joints designed to shed water
● Minimal reliance on single-barrier systems
● Secondary systems installed where practicable, including:
Flashing
Dampproofing
Weeps
Drainage tubes

● Proper allowance for thermal expansion, contraction, and weathering cycles
● Absence of level or horizontal envelope areas that would allow ponding water at roofs,
balconies, and walkways