The Ontario Building Code | Performance Requirements
9.7.4.3. Performance Requirements
(1) Performance grades for windows, doors and skylights shall be selected according to CSA A440S1, "Canadian Supplement to AAMA/WDMA/CSA 101/I.S.2/A440, NAFS - North American Fenestration Standard/Specification for windows, Doors, and Skylights" so as to be appropriate for the conditions and geographic location in which the window, door or skylight will be installed.
(2) windows, doors and skylights shall conform to the performance grades selected under Sentence (1) when tested in accordance with AAMA/WDMA/CSA 101/I.S.2/A440, "NAFS - North American Fenestration Standard/Specification for windows, Doors, and Skylights".
(3) The minimum level of performance required for windows, doors and skylights shall be that of the Performance Class R.
(4) exterior wood doors shall conform to CAN/CSA-O132.2 Series, "wood flush doors" and shall have legibly indicated on them,
(a) the name of the manufacturer,
(b) the standard to which they were produced, and
(c) that they are of an exterior type.
9.7.5. Site-Built windows, Doors and Skylights
In Plain Language
Skylights must meet specific performance requirements addressing structural loads, water tightness, and condensation control, since a horizontal or sloped glazed opening faces different stresses than a vertical window.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.