Intent 1:
For columns exposed to the weather that support
exterior walls or roofs, to limit the probability that the columns
will rust at an excessive rate, which could lead to the premature
failure of the columns
For columns that support
exterior walls or roofs, this is to limit the probability of excessive
deformation or deflection, or compromised air barrier systems, which
could lead to:
- condensation,
- precipitation ingress, or
- compromised thermal performance of components intended
to provide resistance to heat transfer.
This is to limit the probability of:
- an inadequate control of temperatures in interior spaces,
relative humidity, or water accumulation,
- the generation of pollutants from biological growth
or from materials that become unstable on wetting, or
- further compromised integrity of environmental separators,
which could lead to the deterioration of building elements.
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.