Technical Questions

Where and when safety glass is required for single family homes can be confusing. Let’s look very specifically at single family homes and the Ontario building code.

9.6.1.2 Material standards for glass,

Safety glass shall conform to, CGSB 12.1-M Tempered or laminated safety glass, or CGSB 12.11-M Wired safety glass.

9.6.1.4 (6) Glass other than safety glass, shall not be used in shower or bathtub enclosures.

Eg: A window in a shower must be safety glass. Defining whether a window is within the “enclosure” of a tub or shower has often been open to interpretation. Glazing in these conditions are not required to meet guard load requirements unless they meet the location requirements for guards below.

If unprotected (railing etc), a window needs to serve as a guard in the same sense as the wall it is contained in. When the interior floor surface is 600mm/23.6” higher than the exterior grade, OR, the adjacent surface within 1.2M/46.8” of the exterior walking surface has a slope of more than 1 in 2.

Size of the glass and aspect ratios are not referenced in the section on guards. If the product meets above criteria and windowsill is lower than 900mm/35.4” the glazing is subject to guard specifications. A product with a horizontal mullion at 900mm above floor would allow the glazing above the mullion to not be required to meet guard load. Glazing in guards must be designed to withstand human impacts based on Table 9.8.8.2 “Specified loads for guards”. Historically manufacturers simply used safety glass. In BC an increase in the requirement for design and sign off by a professional for guard load glazing is gaining traction. Talk to your engineer about MEPLA software for glass design.

Table 9.6.1.3 G outlines minimum glass area for doors.

9.6.1.4 (1) says “Glass sidelights greater than 500mm/19.68” wide that could be mistaken for doors, glass in storm doors and glass in sliding doors within or at every entrance to a house or an individual dwelling unit” shall be safety glass. The phrase “could be mistaken for doors” is open to interpretation.

Further to this, 9.6.1.4 (2) says, “Except as provided in Sentence (4), glass in entrance doors to houses or individual dwelling units and in public areas, other than the entrance doors described in Sentence (1), shall be safety glass or wired glass of the type described in Sentence (1) where the glass area exceeds 0.5 m2/5.38 sqft AND extends to less than 900mm/35.43” from the bottom of the door.” Shall be safety glass. Sentence 4 refers to glass partitions in public areas.

9.8.8.1 (7) says, “Except as provided in Sentence (8), glazing installed over stairs, ramps and landings that extends to less than 1070 mm/42.12” above the surface of the treads, ramp or landing shall be,”

(a) protected by guards in accordance with this Subsection.

Note, sentence 8 refers to public areas.

A window with a horizontal mullion at 1070mm/42.12” from floor would allow the glazing above the mullion to not meet guard load requirements.

I could not find any reference to windows beside a door and safety glass In the Ontario code. In the BCBC (and NBC) there is a reference A-9.7.5.2 (1) in the Annex, but only notes a consideration for safety glass in windows within 900mm of doors handle. In the VBBL there is a requirement in the main body of the code where windows within 915mm/36.02” of doors (not specifically distance from handles/locks) must be safety or laminated glass. VBBL 9.6.1.4(1) says “Glass sidelights and windows located within 915 mm of doors, and greater than 500 mm wide that could be mistaken for doors,”

I could not find any reference to safety glass for windows replacing doors.