1) This Section applies to crawl spaces whose exterior
walls have less than 25% of their total area above exterior
ground level open to the outdoors.
1) Foundations enclosing crawl spaces shall conform to Section 9.15.
1) Crawl spaces shall be considered to be heated where
the space
a)is used as a hot air plenum,
b)contains heating ducts that are not sealed and insulated to minimize heat loss to the space, or
c)is not separated from heated space in accordance with Section 9.25.
2) Heating of heated crawl spaces shall conform to
Section 9.33.
3) Insulation, an air barrier system and a vapour barrier shall be installed in the walls of heated crawl spaces in accordance with Section 9.25.
1) An access opening of not less than 500 mm by 700 mm
shall be provided to each crawl space where the crawl space
serves a single dwelling unit, and not less than 550 mm by 900 mm for other
crawl spaces.
2) Access openings shall be fitted with a door or hatch,
except when the crawl space is heated and the access opening
into the crawl space is from an adjacent heated space.
1) Unheated crawl spaces shall be ventilated by natural
or mechanical means.
2) Where an unheated crawl space is ventilated by natural
means, ventilation shall be provided to the outside air by not
less than 0.1 m2 of unobstructed vent area for every
50 m2 of floor area.
3) Vents shall be
a)uniformly distributed on opposite sides of the building, and
b)designed to prevent the entry of snow, rain and insects.
1) Heated crawl spaces shall be ventilated in accordance
with Section 9.32.
1) Where equipment requiring service such as plumbing
cleanouts, traps and burners is located in crawl spaces, an
access way with a height and width of not less than 600 mm shall
be provided from the access door to the equipment and for a
distance of 900 mm on the side or sides of the equipment to be
serviced.
1) Except where it can be shown to be unnecessary, the
ingress of water into a crawl space shall be controlled by
grading or drainage.
2) Drainage of foundation walls shall conform to Article 9.14.2.1.
3) Drainage of the ground cover or floor-on-ground in the
crawl space shall conform to Subsection 9.16.3.
4) Drains shall conform to Section 9.14.
1) Where a crawl space is unheated, a ground cover shall
be provided consisting of not less than
a)50 mm of asphalt,
b)100 mm of 15 MPa Portland cement concrete,
c)Type S roll roofing, or
d)0.10 mm polyethylene.
2) Joints in sheet-type ground cover required in Sentence (1) shall be lapped not less than 100 mm and weighted down.
1) Where a crawl space is heated, a ground cover
consisting of not less than 0.15 mm polyethylene sheet
conforming to CAN/CGSB-51.34-M, “Vapour Barrier, Polyethylene Sheet for
Use in Building Construction,” shall be provided.
2) The ground cover required in Sentence (1) shall
a)have its joints lapped not less than 300 mm, and sealed and weighted down, or
b)be covered with a concrete skim coat not less than 50 mm thick.
3) The perimeter of the ground cover required in Sentence (1) shall be sealed to the foundation wall. (See A-9.13.4., A-9.13.4.3., 9.13.4.5. and 9.13.4.7., and A-9.13.4.5.(1) and (2) in Appendix A.)
1) Only crawl spaces under 1-storey portions of dwelling units shall be used as warm-air plenums.
2) Enclosing material in crawl spaces described in
Sentence (1), including insulation, shall have a surface flame-spread rating not greater than 150.
3) Combustible ground cover in crawl spaces described in Sentence (1) shall be protected beneath each register opening with noncombustible material.
4) The noncombustible register protection described in Sentence (3) shall
a)extend not less than 300 mm beyond the projection of the register opening, and
b)have up-turned edges.
(See Appendix A.)