What Part K covers

Approved Document K (commonly known as Part K) deals with protection from falling, collision and impact. For homeowners, the most important section is about glazing. According to the Planning Portal, safety glazing is required in areas where people are most likely to bump into or fall against the glass. These are called “critical locations.”

Where are the critical locations?

The official Part K document (2025 edition) identifies the following zones:

• Glazed doors – all glass within the door itself must be safety glass.
• Side panels next to doors – if within 300 mm of the door edge and below 1500 mm in height.
• Low-level glazing – any glass panel below 800 mm from the finished floor level.
• Bathrooms and showers – because wet floors increase the chance of impact.
• Staircases, ramps, and landings – including glass balustrades and guards.

These requirements are designed to prevent accidents and injuries, and apply whether you are installing large picture windows, shower screens, or shopfront glazing.

Types of safety glass allowed

Part K does not mandate one single product, but it requires compliance with specific British Standards. The two most common types are tempered (toughened) glass and laminated glass, both tested to BS EN 12600 impact classifications.

Glass balustrades and BS 6180

One of the most common applications in modern homes is the use of glass balustrades for staircases, balconies, and terraces. Beyond Part K, these are governed by BS 6180, which specifies minimum heights, line loads, and point loads. The choice of thickness (often 10 mm, 12 mm, or laminated 17.5 mm) depends on the barrier’s location and whether it needs to withstand domestic or public usage.

Designers usually prefer laminated safety glass for balustrades because it maintains integrity even if one ply fails. This ensures that the barrier continues to perform its function until it is replaced.

How to check compliance before ordering

• Confirm with your supplier that the glass is tested to BS EN 12600 and stamped accordingly.
• For toughened glass, look for markings showing compliance with BS EN 12150.
• For balustrades, request structural calculations showing compliance with BS 6180 load requirements.
• Always use a competent installer and, where applicable, notify Building Control.

Costs and practical advice

Tempered glass is usually the most cost-effective choice for domestic doors, shower screens, and low-level glazing. It is stocked in common thicknesses such as 6 mm and 8 mm, which keeps lead times short. Laminated glass is typically more expensive and takes longer to fabricate, but it is essential in overhead applications and barriers. Homeowners often combine both: tempered glass for internal doors and showers, and laminated or tempered-laminated for balustrades and shopfronts.

When planning a project, consider how the glazing will be used in daily life. For example, bathroom glass is exposed to moisture and requires both safety and durability. Choosing tempered glass with an anti-limescale coating can reduce cleaning and extend lifespan.

Conclusion

Building Regulations might seem complicated, but the key message is simple: use the right glass in the right location. Doors, low-level glazing, and bathrooms need safety glass to protect people from harm. Balustrades and overhead glazing require laminated glass to maintain a barrier if broken. By checking for standards such as BS EN 12150 and BS EN 12600, you can be confident your home project is safe and compliant.

For tailored advice, speak to a professional installer and consult official guidance such as Approved Document K. And when you are ready to order, explore our tempered glass cut to size options available for fast UK delivery.