Tempo:
connection to depressurization equipment sealed to maintain the integrity of the air barrier system. The outlet should be clearly labelled to indicate that it is intended for the removal of radon from below the floor-onground. An example of this method would be a sump chamber that is sealed to the air barrier, which can be connected and used to exhaust air from beneath a floor-on-ground.
The second method is more specific and requires a 100 mm (4 in.) layer of clean, granular material under the floor-on-ground and a pipe at least 100 mm (4 in.) in diameter through the floor. The lower end of the pipe extends into the required granular layer. The top of the pipe must be fitted with an airtight cap. If there is a desire to locate the pipe rough-in close to an exterior wall or into the service area of a basement, a normal plumbing pipe can be used to connect the vertical pipe to the center of the sub-floor.
If the sub-floor space is interrupted by internal footings, it is important to ensure that the collection system is capable of depressurizing all areas.
Slabs-on-ground Because slabs-on-ground have requirements similar to those pertaining to basement floor slabs, the steps and precautions described for the latter apply here as well. An important difference is the need to establish the finish floor level at a sufficient height above the natural grade so that the finished grade will provide good drainage away from the house (Figure 49). The top of the slab must be at least 150 mm (6 in.) above finished grade. Remove all debris, stumps and organic matter from the area below the slab and fill voids with compacted granular material to provide a smooth surface free of soft pockets.
49 Independent concrete floor slab and foundation wall
stud air/vapour barrier
metal or vinyl siding
insulation
sheathing membrane
drywall finish flooring concrete slab reinforced
rigid insulation over sheathing and 2 × 4 framing sheathing base flashing 150 mm (6 in.) minimum
well-compacted fill under slab dampproofing floor-to-wall joint and caulking sill gasket
12 mm (1⁄2 in.) cement parging on lath or other protection rigid insulation foundation wall
The second method is more specific and requires a 100 mm (4 in.) layer of clean, granular material under the floor-on-ground and a pipe at least 100 mm (4 in.) in diameter through the floor. The lower end of the pipe extends into the required granular layer. The top of the pipe must be fitted with an airtight cap. If there is a desire to locate the pipe rough-in close to an exterior wall or into the service area of a basement, a normal plumbing pipe can be used to connect the vertical pipe to the center of the sub-floor.
If the sub-floor space is interrupted by internal footings, it is important to ensure that the collection system is capable of depressurizing all areas.
Slabs-on-ground Because slabs-on-ground have requirements similar to those pertaining to basement floor slabs, the steps and precautions described for the latter apply here as well. An important difference is the need to establish the finish floor level at a sufficient height above the natural grade so that the finished grade will provide good drainage away from the house (Figure 49). The top of the slab must be at least 150 mm (6 in.) above finished grade. Remove all debris, stumps and organic matter from the area below the slab and fill voids with compacted granular material to provide a smooth surface free of soft pockets.
49 Independent concrete floor slab and foundation wall
stud air/vapour barrier
metal or vinyl siding
insulation
sheathing membrane
drywall finish flooring concrete slab reinforced
rigid insulation over sheathing and 2 × 4 framing sheathing base flashing 150 mm (6 in.) minimum
well-compacted fill under slab dampproofing floor-to-wall joint and caulking sill gasket
12 mm (1⁄2 in.) cement parging on lath or other protection rigid insulation foundation wall
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