What the glazing rule covers
Part 8.4 of the National Construction Code’s Housing Provisions deals with glazing and human impact. Its application clause says the thickness and type of glazing installed in areas of a building that have a high potential for human impact must comply with the Part, and it defines such an area as one frequented by the occupants during everyday activities in which a person could fall into or against the glazed panel.
The Part adds that it need not be complied with if H1D8(3)(a) is complied with, and the NSW variation of the same clause says the same of NSW H1D8(3)(a).
The rule speaks about the glazing installed in areas of a building where a person could fall into or against the glass. It is not a direction to replace the glass in a home that is already standing; it is what the code asks of the glazing in those places as the work is done.
The places the code names
The Part works through the places a person meets glass in a home. At each one it asks for Grade A safety glazing material, in accordance with its own tables and figures, and then sets out the cases that differ. The table is that list, in the code’s own terms.
| Place | What the code asks | The cases it sets out |
|---|---|---|
| Doors | Glass in doors must be Grade A safety glazing material, with exceptions the code sets out. | Unframed doors, other than those incorporated in shower screens or bath enclosures, must be glazed with toughened safety glass of a minimum nominal thickness of 10 mm, or laminated toughened safety glass of a minimum total thickness of 10 mm. |
| Side panels beside a door | Framed glass, except leadlight panels, in side panels with their nearest vertical sight line less than 300 mm from the nearest edge of the doorway opening must be Grade A safety glazing material, with exceptions the code sets out. | Framed glass panels whose nearest vertical sight line is not less than 300 mm from the nearest edge of the door opening are not side panels for this rule. For a side panel within 300 mm, where its lowest visible sight line is more than 1.2 m above the highest abutting finished floor level, monolithic annealed glass of a minimum thickness of 5 mm and an area of not more than 0.3 m² may be used. |
| Panels low to the floor | Framed glazing on the perimeter of a room where the lowest sight line of the panel is less than 500 mm from the highest abutting finished floor level must be Grade A safety glazing material, with exceptions the code sets out. | Monolithic annealed glass of not less than 5 mm nominal thickness, provided the area of the glazing panel is not more than 1.2 m². |
| Panels that read as openings | A glazed panel located in a building so that it is capable of being mistaken for an unobstructed opening must be glazed with Grade A safety glazing material. | If the presence of glazing in a door, side panel or panel capable of being mistaken for a doorway or opening is not made apparent, the glass must be marked to make it readily visible; and making the glass visible by marking is not a substitute for the use of safety glazing. |
| Kitchens, bathrooms, ensuites and spa rooms | All glazing in these rooms, including shower doors, shower screens, bath enclosures, and associated windows and doors (including cabinet doors), where the lowest sight line is less than 2.0 m above the highest abutting finished level of the floor, of the bottom of the bath, or of the shower base, must be Grade A safety glazing material, with exceptions the code sets out. | The clause reaches associated windows and doors as well as the shower doors, screens and bath enclosures it names. The code notes that care should be taken with showers fitted with safety organic-coated glass and laminated safety glass products that are liable to damage from thermal shock, which occurs when hot water from the shower hits the screen in cold weather. Glass splashbacks used near gas appliances are covered by AS/NZS 5601. |
Which of the two safety glasses a place allows
The Part asks for Grade A safety glazing material, which is the code’s name for the safety glass it wants at these places, rather than a name for one kind of glass. One place where the code itself names toughened and laminated toughened glass is the unframed door: there it allows toughened safety glass of at least 10 mm nominal thickness, or laminated toughened safety glass of at least 10 mm total thickness.
For all glazing in kitchens, bathrooms, ensuites, spa rooms or the like, shower doors, shower screens and bath enclosures included, where the glass comes lower than 2.0 m above the floor, bath or shower base, the code asks for Grade A safety glazing material in framed panels, and for toughened safety glass at least 6 mm thick in panels or doors with any edge exposed. The NSW Government’s page on toughened glass says AS 1288 counts toughened and laminated safety glass as Grade A, and Your Home says laminated glass is often used in the areas of a home most prone to injury from human impact, such as bathrooms, doors, around staircases and in areas close to the floor, where it meets the requirements of safety glass that AS 1288 mandates.
What separates the two when a pane breaks is on the next guide, which takes each one in turn. A bushfire rating can narrow the choice instead. Among its examples of retrofits for an existing home up to and including BAL 29, Building and Energy in Western Australia says glass should be toughened safety glass where windows and external doors are left without metal screens or bushfire shutters; it adds that such work may need a building permit, and that above BAL 29 it sends the owner to a building surveyor or another qualified and experienced practitioner for advice. The Queensland Government says the measures required for new homes in the most extreme fire risk areas will include shutters or toughened glass for windows.
The mark on safety glass
The Part that deals with the identification of safety glass says safety glass must be marked in the form of either permanent etching or a label that cannot be reused once removed. That gives a reader something to look for on a pane: an etch or such a label, or a question for whoever supplied the glass.
Two more guides, and one caution
If a pane in your home sits at one of these places, the useful next question is whether it is safety glass, and which kind: the guide on laminated and toughened glass sets out how each is made and how each is described as breaking. If the window faces a bushfire risk instead, the guide on glass in a bushfire-prone area carries what four states’ official pages say about glass at windows and doors.
Nothing here assesses the glass in any particular home. The rule is the code’s, the places are the code’s, and the code is applied to building work by the people who do it and the authorities that approve it.