Intent 1:
To limit the probability of:
- lintels that are inadequate in size or have an excessive
span, which could lead to the excessive deflection or failure of lintels,
which could lead to the cracking or structural failure of masonry
veneer over openings, or
- an inadequate bearing area between lintels and supported
masonry veneer, which could lead to shear or compression failure of
masonry veneer.
Where masonry units support or are
part of an environmental separator, this is to limit the probability
of:
- excessive moisture transfer through masonry units, or
- deformation or cracking, which could lead to the displacement
or failure of required environmental separation elements.
This is to limit the probability of:
- condensation,
- precipitation ingress,
- moisture ingress,
- excessive heat transfer,
- pollutant ingress, or
- compromised thermal performance of components intended
to resist heat transfer.
This is to limit the probability of:
- an inadequate control of temperatures in 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.