1) This Section applies to floors supported on ground or
on granular fill that do not provide structural support for the superstructure.
1) Floors-on-ground that support loads from the
superstructure shall be designed in conformance with Part 4.
1) All spaces within dwelling units, except crawl spaces, shall be provided with a floor-on-ground, where
a)access is provided to the space, and
b)a floor supported by the structure is not provided.
1) Dampproofing and waterproofing shall conform to
Section 9.13.
1) Except as provided in Sentence (2), not less than 100 mm of coarse clean granular material shall be placed beneath floors-on-ground and where the requirements of Article 9.13.8.2. are employed the granular material shall not contain more than 10% of material that will pass a 4 mm sieve. (See Clause 9.13.4.1.(4)(b), Article 9.13.4.6., and A-9.13.4.6. in Appendix A.)
2) Granular material need not be installed under
a)slabs in garages, carports or accessory buildings,
b) buildings of industrial occupancy where the nature of the process contained therein permits or requires the use of large openings in the building envelope even during the winter, or
c) buildings constructed in areas where it can be demonstrated that soil gas does not constitute a hazard.
1) Material that is susceptible to changes in volume
due to variations in moisture content or
chemical-microbiological oxidation shall not be used as fill beneath floors-on-ground in a concentration that will damage the
building to a degree that would adversely affect its stability or the performance
of assemblies. (See also Article 9.4.4.4. and A-9.4.4.4.(1) in Appendix A.)
2) Material that is susceptible to changes in volume
due to freezing shall not be used as fill beneath floors-on-ground that will be subjected to freezing
temperatures. (See also Article 9.4.4.4. and A-9.4.4.4.(1) in Appendix A.)
3) Except as provided in Sentence (4), fill beneath floors-on-ground shall be compacted.
4) Fill beneath floors-on-ground need not be compacted where the material is
clean coarse aggregate containing not more than 10% of material
that will pass a 4 mm sieve.
1) Except as provided in Article 9.16.3.2. or where it can be shown to be unnecessary,
ingress of water underneath a floor-on-ground shall be prevented
by grading or drainage.
1) Where groundwater levels may cause hydrostatic pressure beneath a
floor-on-ground, the floor-on-ground shall be
a)a poured concrete slab, and
b)designed to resist such pressures.
1) When floor drains are required (see Section 9.31.), the floor surface shall be sloped so that no water can
accumulate.
1) The finished surface of concrete floor slabs shall be
trowelled smooth and even.
2) Dry cement shall not be added to the floor surfaces to
absorb surplus water.
1) When a topping course is provided for a concrete floor
slab, it shall consist of 1 part cement to 2.5 parts clean, well
graded sand by volume, with a water/cement ratio approximately
equal to that of the base slab.
2) When concrete topping is provided, it shall not be
less than 20 mm thick.
1) Concrete slabs shall not be less than 75 mm thick
exclusive of concrete topping.
1) A bond-breaking material shall be placed between the
slab and footings or rock.
1) Floors-on-ground constructed of wood shall conform to
CAN/CSA-S406, “Construction of Preserved Wood Foundations.”