Intent 1:
To limit the probability of the inadequate splicing
of ceiling joists, which could lead to ceiling joist splices being
unable to resist the tension forces imposed by expected gravity and
lateral loads on rafters, which could lead to the lower end of rafters
moving outward, which could lead to:
- the failure of roof rafters or joists, or supporting
walls, or
- the excessive deflection of roof rafters or joists,
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:
- condensation,
- precipitation ingress,
- excessive heat transfer,
- pollutant ingress, or
- compromised thermal performance of components intended
to resist heat transfer.
This is to limit the probability of:
- inadequate control of temperatures of interior spaces,
drafts, 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 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.