Back9.18.2.1.(2)

ATTRIBUTION:

Functional Statement:

F51

To maintain appropriate air and surface temperatures.

F63

To limit moisture condensation.

F42

To resist the entry of vermin and insects.

F61

To resist the ingress of precipitation, water or moisture from the exterior or from the ground.

Objective:

OS2.3, OS2.3

 

APPLICATION:

Closures for access openings for crawl spaces whose exterior walls have less than 25% of their total area above exterior ground level open to the outdoors, where:
  • crawl spaces are unheated and access is from the exterior,
  • crawl spaces are unheated and access is from the interior, or
  • crawl spaces are heated and access is from the exterior.
This applies to buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To limit the probability of unprotected access openings, which could lead to:
  • where crawl spaces are unheated and access is from the interior, moisture transfer from the interior, or
  • where crawl spaces are heated or unheated and access is from the exterior:
    • the ingress of precipitation,
    • an infestation of insects or vermin, or
    • compromised thermal performance of components intended to provide resistance to heat transfer.
This is to limit the probability of:
  • an inadequate control of the temperature of interior spaces, relative humidity or drafts,
  • the generation of pollutants from biological growth or from materials that become unstable on wetting, or
  • deterioration, which could lead to compromised integrity of environmental separators or of elements protected by the 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.

ATTRIBUTION:

Functional Statement:

F63

To limit moisture condensation.

F42

To resist the entry of vermin and insects.

F61

To resist the ingress of precipitation, water or moisture from the exterior or from the ground.

Objective:

OS2.3, OS2.3

 

APPLICATION:

Closures for access openings for crawl spaces whose exterior walls have less than 25% of their total area above exterior ground level open to the outdoors, in buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To limit the probability of unprotected access openings, which could lead to:
  • where crawl spaces are unheated and access is from the interior, moisture transfer from the interior, or
  • where crawl spaces are heated or unheated and access is from the exterior:
    • the ingress of precipitation, or
    • an infestation of insects or vermin.
This is to limit the probability of compromised structural integrity, which could lead to:
  • structural failure, or
  • for environmental separators or elements supporting an environmental separator, the displacement or failure of required environmental separation elements, which could lead to the deterioration of building elements.
This is to limit the probability of harm to persons.

ATTRIBUTION:

Functional Statement:

F42

To resist the entry of vermin and insects.

Objective:

OH2.4, OH2.5

 

APPLICATION:

Closures for access openings for crawl spaces whose exterior walls have less than 25% of their total area above exterior ground level open to the outdoors, in buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To limit the probability of unprotected access openings, which could lead to the ingress of insects or vermin, which could lead to unsanitary conditions, which could lead to harm to persons.