Flagship guide · 11 min read
The Complete Guide to Glass Specification
The frame gets most of the attention, but the glass does most of the work. This is our full guide to choosing it properly.
Safety Glass: What the Regulations Require
Building Regulations set out specific locations where safety glass is mandatory. Here is what that means in practice.
3 min read
Safety glazing is one of the few areas of glass specification that is not a matter of taste or budget — it is a legal requirement in defined locations under Approved Document K of the Building Regulations. Understanding where it applies, and what qualifies as safety glass, avoids awkward surprises at building control sign-off.
This guide sets out the critical locations, the two types of glass that satisfy the requirement, and how they are typically marked and checked.
Critical locations under Part K
- Glazing in a door, and glazing within 300mm of a door edge, up to 1500mm above floor level
- Glazing in a wall or partition below 800mm from floor level in any room
- Glazing between 800mm and 1500mm above floor level in rooms with a higher risk of impact, such as bathrooms
- Glazed side panels adjacent to doors, regardless of the frame they sit in
What qualifies as safety glass
| Toughened glass | Laminated glass | |
|---|---|---|
| How it satisfies Part K | Breaks into small, blunt granules rather than sharp shards | Interlayer holds broken glass together, preventing a fall-through hazard |
| Strength | Around five times stronger than standard glass | Similar base strength, with added post-breakage integrity |
| Extra benefits | None beyond safety | Improved security and acoustic performance |
| Marking | Permanent etched mark in a corner of the pane | Often marked similarly, confirming compliance |
Checking compliance
Safety glass is required to carry a permanent marking, usually etched discreetly into a corner of the pane, confirming the standard it meets (BS EN 12150 for toughened, BS EN ISO 12543 for laminated). This marking should remain visible for the life of the window and is checked as part of a FENSA or Certass self-certification, or by building control on a project without a competent person scheme.
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