Intent 1:
To limit the probability of:
- the veneer being unable to support its own weight or
lateral loads,
- insufficient bonding area between ties and mortar in
loadbearing or non-loadbearing masonry cavity walls, which could lead
to an inability to resist lateral, tensile and compressive loads,
or
- insufficient bond strength between masonry veneer units
in loadbearing or non-loadbearing cavity walls, which could lead to
an inability to resist tensile stresses due to lateral loads.
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,
- 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 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.
Intent 2:
To exempt masonry veneer in which the units are
not designed to provide vertical support to each other from the minimum
thickness requirement of this Sentence.