# The Ontario Building Code | Glazed Openings in Exposing Building Face

9.10.15.4. Glazed openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings in Exposing building Face

(1) Except as provided in Sentences (3) to (5), the maximum area of glazed openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings in an exposing building face shall,

(a) conform to Table 9.10.15.4.,

(b) conform to Subsection 3.2.3. as if the glazed openings were unprotected openings, or

(c) where the limiting distance is not less than 1.2 m, be equal to or less than the limiting distance squared.

Table 9.10.15.4.
Maximum Area of Glazed Openings in Exterior Walls of Houses

Forming Part of Sentences 9.10.15.4.(1) and (2)

 Item Column 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Maximum Total Area of Exposing Building Face, m² Maximum Aggregate Area of Glazed Openings, % of Exposing Building Face Area Limiting Distance, m Less than 1.2 1.2 1.5 2 2.5 3 4 6 8 10 12 16 20 25 1. 10 0 8 12 21 33 55 96 100 — — — — — — 2. 15 0 8 10 17 25 37 67 100 — — — — — — 3. 20 0 8 10 15 21 30 53 100 — — — — — — 4. 25 0 8 9 13 19 26 45 100 — — — — — — 5. 30 0 7 9 12 17 23 39 88 100 — — — — — 6. 40 0 7 8 11 15 20 32 69 100 — — — — — 7. 50 0 7 8 10 14 18 28 57 100 — — — — — 8. 100 0 7 8 9 11 13 18 34 56 84 100 — — — 9. Over 100 0 7 7 8 9 10 12 19 28 40 55 92 100 —

(2) Where the limits on the area of glazed openings are determined for individual portions of the exterior wall, as described in Subclause 9.10.15.2.(1)(b)(iii), the maximum aggregate area of glazed openings for any portion shall not exceed the values in the row of Table 9.10.15.4. for the total area of the entire exposing building face based on the limiting distance of the individual portion.

(3) The limits on the area of glazed openings shall not apply to the exposing building face of a dwelling unit facing a detached garage or accessory building, where,

(a) the detached garage or accessory building serves only one dwelling unit,

(b) the detached garage or accessory building is located on the same property as that dwelling unit, and

(c) the dwelling unit served by the detached garage or accessory buildingis the only major occupancy on the property.

Note: On July 1, 2017, Sentence 9.10.15.4.(3) of Division B of the Regulation is revoked and the following substituted: (See: O. Reg. 139/17, s. 113)

(3) The limits on the area of glazed openings shall not apply to the exposing building face of a house facing a detached garage or accessory building, where,

(a) the detached garage or accessory building serves the house or an individual dwelling unit in the house,

(b) the detached garage or accessory building is located on the same property as the house, and

(c) the houseis the only major occupancy on the property.

(4) Except as provided in Sentence (5), openings in a wall having a limiting distance of less than 1.2 m shall be protected by closures, of other than wired glass or glass block, whose fire-protection rating is in conformance with the fire-resistance rating required for the wall.

(5) An opening in an exposing building face not more than 130 cm2 shall not be considered an unprotected opening.