Although moisture ingress into an envelope assembly can
be from initial construction moisture, humidity sources or exterior sources such as rain, the majority of
performance problems have resulted
from failure to control exterior moisture sources.
Most water enters the wall assembly at the interface
details between wall components or at key penetrations.á
Key problem details include window perimeters, perimeters of decks,
balconies and walkways, and
saddle connections.á Water enters the
wall assembly at details and stays in the wall long enough to result in deterioration.
One water management strategy is to create a face
seal.á This strategy attempts to
eliminate paths for exterior
moisture at the face of the cladding.á
The use of a face seal system must be limited to an environment where very little water will impact on
the surface of the cladding and the risk of water penetration past the cladding is minimal.