Back9.19.1.4.(1)

ATTRIBUTION:

Most technical provisions of the BC Fire Code describe how the code’s objectives and functional statements are achieved. However, some provisions, like this one, do not relate directly to a code objective. The following analysis is provided to assist in understanding of the provision.

 

APPLICATION:

Ventilation of lower portions of mansard or gambrel roofs of buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To exempt from the application of Articles 9.19.1.1. to 9.19.1.3., roof configurations where:
  • heat and moisture transfer into or out of the space (caused by air pressure differences across the building envelope induced by stack effect) is reduced because the lower portion of the roof is close to the neutral pressure plane, and
  • the likelihood of snow accumulation and ice damming is limited.