Intent 1:
To limit the probability that the performance of
windows, doors and skylights will fall significantly below expectations
with respect to:
- resistance to air pressure loads,
 - resistance to structural loads,
 - resistance to water penetration loads,
 - resistance to snow loads on skylights or where windows
have sloped or near-horizontal components,
 - resistance to forced entry, and
 - ease of operation.
 
This is to limit the probability of:
- excessive air leakage,
 - excessive heat loss or gain,
 - condensation,
 - precipitation and melt water ingress,
 - insufficient protection against the ingress of insects
and vermin, or
 - inoperability or excessive difficulty in operating doors
and openable windows.
 
This is to limit the probability of:
- the inadequate control of temperatures of interior spaces,
relative humidity, drafts, or water accumulation,
 - the generation of pollutants from biological growth
or from materials that become unstable on wetting,
 - deterioration, which could lead to compromised integrity
of exterior wall assemblies, or
 -  inadequate ventilation where windows, doors and skylights
provide required non-heating-season ventilation.
 
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.