Intent 1:
To limit the probability of uncontrolled air leakage
and uncontrolled vapour diffusion between walls and windows or doors,
and between ceilings and skylights, which could lead to
- condensation on the surface of building elements or
within building elements,
- excessive heat loss or gain,
- precipitation ingress, or
- ingress of insect and vermin.
This is to limit the probability of:
- the 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 compromised integrity
of assemblies acting as 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.