ATTRIBUTION:
Functional Statement:
F61
To resist the ingress of precipitation, water or
moisture from the exterior or from the
ground.
Objective:
OH1.1, OH1.2, OH1.3
APPLICATION:
Grades of eastern white cedar shingles installed as
undercoursing to provide protection from precipitation on vertical assemblies
exposed to precipitation.
INTENT:
To limit the probability of defects such as loose knots,
large holes, cross-grain areas or checks, which could lead to unevenness or
compromised integrity of the undercoursing, which could lead to a reduction
in the watertightness of shingle cladding, which could lead to precipitation
ingress.
This is to limit the probability of:
- the inadequate control of relative humidity or water accumulation,
- the generation of pollutants from biological growth or from
materials that become unstable on wetting, or
- deterioration, which could lead to compromised integrity of
environmental separators.
This is to limit the probability of:
- negative effects on the air quality of indoor spaces,
- the inadequate thermal comfort of persons, and
- contact with moisture.
This is to limit the probability of harm to persons.