Where Tempered Glass Is Required by Code in California (2026)

In California, tempered glass (or laminated glass meeting the same standard) is required by code in a defined set of "hazardous locations" — most commonly in and near doors, in and around tubs and showers, next to stairways and landings, and in windows whose glass sits close to the floor. These rules come from Section 2406.4 of the 2025 California Building Code (CBC), which took effect January 1, 2026. If glass sits in one of those locations, ordinary annealed glass is not legal there, even as a like-for-like replacement.

I'm John, owner of Colfax Glass. The single most common reason a window or glass-door project fails final inspection in Placer and Nevada County is safety glazing in the wrong place — either a hazardous-location pane that was replaced with annealed glass, or a tempered pane whose permanent etch mark got stripped off before the inspector arrived. Homeowners are often surprised by how many everyday openings the code treats as hazardous. A window three feet from a door. The glass beside a stair. The little window over the tub. All of them can trigger the requirement.

This guide walks through each hazardous location in CBC Section 2406.4 in plain language, with the dimensions that actually decide whether a given pane needs safety glass. It is written for foothill homeowners and remodelers who want to know before they order — because tempered glass cannot be cut or drilled after it is made, and getting the spec wrong means re-ordering the whole pane.

Safety glazing is glass that has been treated or built so that, if it breaks, it does not produce the large dagger-like shards that ordinary annealed glass creates. Two products satisfy the code: tempered glass and laminated glass. Both must meet the impact standard in CPSC 16 CFR 1201 (Category I or II depending on size) or ANSI Z97.1.

Tempered glass is heat-treated to roughly four to five times the strength of annealed glass. When it does break, it crumbles into small, blunt fragments rather than sharp pieces. It is the default choice for most residential hazardous locations because it is cost-effective and widely stocked.

Laminated glass bonds two glass sheets around a plastic interlayer. When it breaks, the interlayer holds the fragments in place. It satisfies the same safety-glazing requirement and is preferred where fallout protection matters — overhead glazing, some railing infill, and locations where you also want security or sound benefits. For a side-by-side comparison of the two products and their costs, see our tempered vs. laminated glass guide.

The critical detail for inspection: every piece of safety glazing must carry a permanent, legible manufacturer's mark identifying the glass type, thickness, and the safety standard it meets. That mark is etched, sandblasted, or ceramic-fired into a corner and cannot be removed. If an inspector cannot find the mark, the glass fails — even if it genuinely is tempered.

All glass in a door is a hazardous location, full stop. That includes the glass panel in a swinging door, the lites in a French door, the fixed and operable panels of a sliding patio door, the glass in a folding or bifold door, and storm and screen door glazing. There is no size exemption — a small decorative lite in an entry door needs safety glass just like a full patio-door panel.

This is the one most people already know, but the practical trap is replacement glass. When a glass entry-door lite or a patio-door pane breaks and gets replaced, the new pane must again be safety glazing. Dropping in an annealed pane because it was cheaper or faster is a code violation and a genuine injury risk.

Commercial storefront doors follow the same rule under CBC Section 2406, and for storefronts every door lite and adjacent sidelite is safety-glazed as a matter of course. Our commercial glass repair work treats every door and near-door panel as tempered or laminated by default.

This is the requirement that surprises homeowners most. Glass in a fixed or operable panel next to a door is a hazardous location when it meets all of these: the nearest vertical edge of the glass is within 24 inches of the door in a closed position, and the bottom edge of the glass is less than 60 inches above the floor. In plain terms: a window whose glass comes within two feet of a door edge, where you could reach or fall through it near the door, needs safety glazing.

This is why sidelites — the tall narrow windows flanking a front door — are almost always tempered. It is also why a window installed close to a swinging door, or the fixed glass beside a slider, frequently triggers the requirement even though it is a "window," not a "door."

There is a relief valve in the code: if there is a wall or permanent barrier between the door and the glass, or if the glass is on a wall perpendicular to the door on the latch side in certain configurations, the requirement can be relieved. But those exceptions are narrow and easy to misread. When we measure a window opening near a door in a foothill home, we default to assuming the pane is hazardous unless the geometry clearly exempts it — re-ordering a tempered pane after a failed inspection costs far more than speccing it right the first time.

Glazing in and around bathtubs, showers, hot tubs, saunas, steam rooms, and indoor pools is a hazardous location where the bottom exposed edge of the glass is less than 60 inches above the standing or walking surface. This covers the obvious cases — the glass panels and door of a shower enclosure — and the less obvious ones, like a window installed in a tub-shower wall.

That small window over the tub is a frequent surprise. If its glass sits below 60 inches above the tub floor or standing surface, it is a hazardous location and needs safety glazing regardless of the window's size. Many older foothill homes have an original annealed single-pane window right in the shower surround; when we replace it, the new pane must be tempered.

Frameless and semi-frameless shower enclosures use tempered glass by definition — the thick 3/8-inch and 1/2-inch panels are all tempered safety glass. The code requirement and the product reality line up cleanly here, but the near-tub window is the piece homeowners forget.

A window does not have to be near a door or a tub to require safety glass. A large pane low to the floor is a hazardous location in its own right when it meets all four of these conditions: the individual pane is larger than 9 square feet, the bottom edge is less than 18 inches above the floor, the top edge is more than 36 inches above the floor, and there is a walking surface within 36 inches of the glass.

This is the classic floor-to-near-floor picture window or large fixed pane in a living room, stairwell, or hallway. The logic is straightforward: a big pane you could walk or fall into, whose glass runs from near the floor up past waist height, is exactly the kind of glass that causes serious lacerations when someone trips into it. The code pulls those panes into the safety-glazing requirement.

All four conditions have to be met. A large pane whose bottom edge sits above 18 inches — say, over a kitchen counter or a knee wall — does not trigger this particular rule (though it may trigger another). A small pane under 9 square feet does not trigger it. This is one of the places where the exact dimensions decide the answer, so measure before you assume.

Glazing next to stairways, ramps, and landings is a hazardous location because a fall on stairs that carries someone into glass is among the most dangerous glass-injury scenarios. Under the code, glazing where the bottom edge is less than 36 inches above the plane of an adjacent walking surface on a stairway, landing, or ramp is a hazardous location. Glazing within a 60-inch horizontal arc of the bottom tread of a stairway, less than 60 inches above the nose of the tread, is also hazardous.

In foothill homes with split-level entries, open stair runs, and daylight basements, this rule catches a lot of glass — the window on a stair landing, the fixed pane alongside an open stringer, the glass at the bottom of a run near the front door. Guards and railings that use glass infill panels are separately required to be safety glazing as structural guards, which we cover in our glass railing installation guide.

There is an exception for glazing protected by a compliant guard or railing where the glass is more than 18 inches from the railing, but as with the near-door exceptions, it is narrow. On a stair project we treat adjacent glass as hazardous unless the geometry clearly clears it.

Not every low or large window is a hazardous location, and it helps to know the common cases where annealed glass is still legal — because tempered glass costs more and there is no reason to over-spec.

A standard double-hung or casement window in a bedroom or living room wall, set at a normal sill height (above 18 inches), not within 24 inches of a door, and not beside a tub or stair, is generally not a hazardous location. It can be ordinary annealed insulated glass. Most of the windows in a typical house fall here.

Decorative glazing — leaded, faceted, or carved glass used decoratively — has a specific exception in some configurations, though it is rarely worth relying on for a new install. Glazing in the walls of certain agricultural or storage structures may also be exempt.

Egress is a separate matter from safety glazing. A bedroom egress window has to meet the clear-opening dimensions of the California egress window requirements, but meeting egress does not by itself require tempered glass unless the window also sits in a hazardous location. The two codes overlap on some openings and are independent on others — which is exactly why a project-level review beats guessing pane by pane.

In Placer County and Nevada County, the building inspector checks safety glazing at the final inspection on any permitted window, door, or remodel project. The inspector is looking for two things: that every hazardous location has safety glass, and that every safety-glazed pane still shows its permanent manufacturer's mark.

The most common correction is a stripped mark. A trim carpenter or the homeowner peels the etched or applied label off for a cleaner look before the inspector arrives, and now the inspector cannot verify the glass. The fix is either a signed installer certification documenting each unit or a product documentation package from the supplier — a paperwork scramble that delays sign-off. Leave the marks on until after final.

The second correction is an annealed pane in a hazardous location, almost always on a replacement where someone swapped in cheaper glass. That one cannot be papered over — the glass has to be replaced with a properly marked safety-glazed unit, and tempered lead times mean the project sits for several days to a week.

When we scope a window or glass project in the foothills, we map every opening against the Section 2406.4 hazardous locations before ordering, so the tempered panes are correct on the first delivery and the marks are intact at final. If you want your project reviewed against the 2026 code before you buy glass, request a free project review and we will flag every pane that needs safety glazing.