Fire Ratings

Fire Safety Compliance and Testing for Patent Glazing in the UK.

fire ratings for patent glazing

In the UK, Building Regulations Approved Document B (2006 edition, amended 2007) outlines fire safety rules for buildings. Section B4 addresses external fire spread, covering roofs and walls, requiring compliance with BS476 Part 3 (typically AA and AB) or BS EN 13501 Part 5 (typically BROOF(t4)) fire resistance standards.

Roofs with non-combustible surface finishes, as specified in European Commission Directive 2000/553/EC, meet BROOF(t4) regulations without testing.

Understanding fire ratings for patent glazing is essential to ensure that all glazing systems meet the necessary safety standards and regulatory requirements. Standard Patent Glazing holds an AA Fire rating to BS476 Part 3, the highest rating available, surpassing BROOF(t4) requirements set out in BS EN 13501 Part 5.

 

Farringdon underground station skylights

Fire ratings

All of our sloping patent glazing systems have a designation AA as defined in BS 476: Part 3 when they are installed with an infill such as 6mm wired cast glass or other glasses of at least 4mm thick.

If elements of the structure have need for a level of fire resistance when tested in accordance with BS 476: Parts 20 and 22, certain types of patent glazing will be suitable. These may either be tested or approved as ‘deemed to satisfy’ by fire authorities or local authority building inspectors.

A joint venture by the Patent Glazing Contractors Association and Pilkington Glass Ltd was organised to test the heat resistance of patent glazing when subjected to smoke temperatures. This test was carried out at Warrington Fire Research Centre and produced the following results.

The test sequence attempted the following furnace temperatures:

  1. 300°C for 30 minutes
  2. 400°C for 15 minutes
  3. 500°C for 15 minutes
  4. 600°C for 30 minutes

The results demonstrated that all aluminium and lead covered steel (Heritage) glazing bars should perform adequately at smoke temperatures up to 600°C. Laminated glass of nominal 6.4mm thickness remained intact up to 400°C, and toughened glass of nominal 6mm thickness remained intact at 600°C, highlighting the importance of selecting appropriate materials when considering fire ratings for patent glazing to ensure compliance with fire safety standards.