Intent 1:
To limit the probability of:
- excessive width, which could lead to excessive shrinkage,
which could lead to:
- buckling or tearing of roofing, or
- excessively wide gaps between boards, which could lead
to puncturing of roofing,
- unsupported end joints, which could lead to an inability
to resist point loads from foot traffic, which could lead to differential
deflection of unsupported sheathing board ends, which could lead to
damage to roofing, and
- aligned end joints, which could lead to discontinuity
in the roof structure, which could lead to an inability to resist
expected lateral or gravity loads, which could lead to excessive deflection,
which could lead to damage to roofing.
Where wood-frame construction supports or is part of an
environmental separator, this is to limit the probability of the displacement
or failure of required environmental separation elements, which could
lead to:
- precipitation ingress, or
- compromised thermal performance of components intended
to resist heat transfer.
This is to limit the probability of:
- an inadequate control of temperatures of interior spaces
or water accumulation,
- the generation of pollutants from biological growth
or from materials that become unstable on wetting, or
- deterioration, which could lead to further 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.