The Ontario Building Code | Required Soil Gas Control

9.13.4.2. Required soil Gas Control

(1) Except as provided in Sentence (2), all wall, roof and floor assemblies in contact with the ground shall be constructed to resist the leakage of soil gas from the ground into the building.

(2) Construction to resist leakage of soil gas into the building is not required for,

(a) garages and unenclosed portions ofbuildings,

(b) buildingsconstructed in areas where it can be demonstrated that soilgas does not constitute a hazard, or

(c) buildings that contain a single dwelling unit and are constructed to provide for subfloor depressurization in accordance with MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control".

Note: On July 1, 2017, Clause 9.13.4.2.(2)(c) of Division B of the Regulation is revoked and the following substituted: (See: O. Reg. 139/17, s. 120 (1))

(c) houses that are constructed to provide for subfloor depressurization in accordance with MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control".

(3) Wheresoil gas control is required, a soil gas barrier shall be installed at walls and roofs in contact with the ground according to MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control".

(4) Wheresoil gas control is required, it shall consist of one of the following at floors in contact with the ground:

(a) a soil gas barrier installed according to MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control", or

(b) where the buildingcontains a single dwelling unit only, a subfloor depressurization system installed according to MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control".

Note: On July 1, 2017, Clause 9.13.4.2.(4)(b) of Division B of the Regulation is revoked and the following substituted: (See: O. Reg. 139/17, s. 120 (2))

(b) for houses,a subfloor depressurization system installed according to MMAH Supplementary Standard SB-9, "Requirements for Soil Gas Control".