Safety glazing is decided opening by opening, from the plan and the elevation. Glass is made to order, so it is worth settling before the order goes in.
The requirements are set out in Section R308 of the California Residential Code and Chapter 24 of the California Building Code. Both work the same way: they list the locations where safety glazing is required, and glazing in one of those locations has to meet the standard.
Tempered or laminated
The code calls for safety glazing. Two products meet it:
- Tempered glass, heat treated so it breaks into small blunt pieces. The more common choice, on cost.
- Laminated glass, two lites bonded to an interlayer that holds the fragments in place.
Either satisfies the requirement. Laminated is worth considering where acoustic performance or security is also a requirement for the opening, since one piece of glass then answers both.
The eight locations that require safety glazing
1. Glass in a door. Any swinging, sliding or bifold door, regardless of size or height.
2. Glass beside a door. Within 24 inches of the door edge when closed, where the bottom of the glass is under 60 inches above the floor.
3. Large windows close to the floor. Where all four of these are true together: the pane is larger than 9 sq ft, the bottom edge is under 18 inches above the floor, the top edge is over 36 inches above the floor, and a walking surface is within 36 inches.
4. Glass railings and guards. Including infill panels.
5. Bathrooms. Tubs, showers, saunas, steam rooms and whirlpools: the enclosure itself, and any wall facing it within 3 feet, where the bottom of the glass is under 60 inches above the floor.
6. Pools and spas. Within 5 feet of the water's edge, where the bottom of the glass is under 60 inches above the deck.
7. Stairs, landings and ramps. Within 36 inches of the walking surface, where the bottom of the glass is under 60 inches above it.
8. The bottom of a stair. Within 60 inches of the bottom tread, where the glass is under 60 inches above the nosing.
A closer look at the large-window rule
Rule 3 is the only one with several conditions attached, so it is worth setting out on its own. All four apply together.
Drawn to scale, the three height and distance conditions look like this:
The practical effect is that pane size and sill height are assessed together with what is on the floor in front of the window. A pane under 9 sq ft is outside the rule, and so is a window with no walking surface within 36 inches of it.
Exceptions worth knowing
Several of the rules carry exceptions. Three come up often enough to be worth naming:
- Glass on the fixed side of a patio door is exempt from rule 2.
- A protective horizontal rail removes rule 3. It needs to be at least 1.5 inches high, set 34 to 38 inches above the walking surface, and able to resist a 50 pound load without contacting the glass.
- Openings too small to pass a 3 inch sphere are exempt from rule 1, as is decorative glass.
There are others, including provisions for glass protected by an intervening barrier and for outboard panes well above grade. They are worth checking against the specific condition rather than assumed.
How this sits with the other requirements
Safety glazing is one of four rules that can apply to the same opening, and they apply alongside each other:
- Safety glazing, by the locations above
- Title 24 energy targets, set by climate zone
- Egress, where the opening serves a sleeping room
- Fire zone glazing, where the parcel is in a WUI area
There is a useful overlap between two of them. A parcel in a fire hazard zone already calls for an insulating unit with at least one tempered pane, which satisfies the safety glazing requirement in the same build.
Specifying it
We can read a window schedule against these locations and tell you which units need safety glazing, which do not, and where laminated is worth considering over tempered because something else on the project is asking for it as well.
Bring floor plans and elevations with the openings marked. Showrooms in Brentwood, Irvine, San Diego, and Santa Barbara, by appointment.
Common questions
When does a window need tempered glass?
When it falls in one of the locations the code lists. For an ordinary window away from doors, stairs and water, that means four conditions holding together: the pane is larger than 9 square feet, its bottom edge is under 18 inches above the floor, its top edge is over 36 inches above the floor, and a walking surface is within 36 inches. A window that does not meet all four is not covered by that rule.
Does glass in a door have to be tempered?
Yes. Glazing in swinging, sliding and bifold doors requires safety glazing regardless of size or height. Glass beside a door is covered separately, within 24 inches of the door edge when closed and under 60 inches above the floor.
What are the requirements around bathrooms and pools?
For tubs, showers, saunas, steam rooms and whirlpools, safety glazing is required in the enclosure itself and in any wall facing it within 3 feet, where the bottom of the glass is under 60 inches above the floor. For pools and spas, it applies within 5 feet of the water's edge where the glass is under 60 inches above the deck.
Is laminated glass acceptable instead of tempered?
Yes. The code calls for safety glazing, and both tempered and laminated glass satisfy it. Tempered is the more common choice on cost. Laminated is often worth considering where acoustic performance or security is also a requirement, since one piece of glass then answers both.
Can safety glazing be avoided on a large window?
There is a provision for it. A horizontal rail at least 1.5 inches high, set 34 to 38 inches above the walking surface and able to resist a 50 pound load without contacting the glass, removes the requirement for the large-window case. It is a design decision rather than a workaround, and it has to be detailed properly.
The locations described here are drawn from Section R308 of the California Residential Code and Chapter 24 of the California Building Code. The two codes differ on some provisions, and jurisdictions adopt with local amendments. Code is revised on a three-year cycle. Confirm the edition in force and the figures that apply to your project with the building department having authority. Several provisions carry exceptions beyond those noted above. This is a specification reference, not a code compliance opinion.