Position of sheet and panel-type materials relative
to the thermal insulation, in
buildings to which Part 9 applies [see
Sentence
1.3.3.3.(1) of Division A for application
of Part 9], where:
- the materials:
- have an air leakage characteristic less than 0.1 L/(s•m2)
at 75 Pa,
- have a water vapour permeance less than 60 ng/(Pa•s•m2),
and
- are installed in a building assembly that is required to be insulated (see Article
9.25.2.1.),
- the mild climate indicator determined in accordance with Sentence
9.25.1.2.(6) is greater than 6 300, and
- the intended use of the interior space:
- requires the indoor relative humidity to be maintained above
35% over the heating season, and the ventilating and air-conditioning system
is designed to maintain that relative humidity, or
- will result in an average monthly indoor relative humidity
above 35% over the heating season, and the ventilating and air-conditioning
system does not have the capacity to reduce the average monthly relative humidity
to 35% over that period.