What are fire regulations?
Fire safety regulations are a set of practices intended to reduce the destruction caused by fire. Fire safety measures include those that are intended to prevent the ignition of an uncontrolled fire, and those that are used to limit the development and effects of a fire after it starts. Following the Grenfell disaster in 2017, many changes have been made to the fire safety regulations in relation to high-rise buildings. One amendment to Approved Document B, in particular, has affected the balustrading on balconies when at height. The amendment banned the use of all combustible materials on the external face of buildings over 18m tall.
What is the required fire rating needed for products to be compliant?
To be compliant, materials have to achieve a fire classification of A1 or A2-s1 classified, in accordance with BS EN 13501-1:2007 + A1:2009. When materials are given an A1 or A2 fire rating, it essentially gives them the ‘non-combustible’ seal of approval. A1 rated materials are completely non-combustible, while A2 rated materials have very limited combustibility. A1 materials have no contribution to fire, and A2 materials have limited contribution to fire. Toughened glass by itself meets the requirements for being A1 fire rated.
A number of items were excluded from the ban, including window frames and window glass. However, these exclusions didn’t extend as far as including laminated glass in balustrades.
How does this affect balustrades?
The primary reason for a balustrade is to protect an edge. When protecting a drop, there must still be a temporary barrier in place if a panel of glass breaks. If there is a handrail on the balustrade, then this will form a temporary barrier. However, if the balustrade is frameless, then we recommend that toughened and laminated glass is used, so that there is a temporary barrier in place should the panel break. The PVB or SGP interlayer holds the broken pane together, until it is safe and convenient to replace the panel.
Whilst it is recognised across the industry that toughened and laminated glass is considerably safer in balustrades, fire regulations bans the use of laminated in buildings over 18m. This is because, in isolation, a PVB or SGP interlayer is flammable. However, oxygen has to be present for a fire to burn, and once sandwiched between 2 panels of toughened glass, there is no way the interlayer is going to burn. Common sense and logic indicate that toughened and laminated glass will not be combustible when looking at the whole product holistically. However, safety regulations rule otherwise, so at the minute toughened & laminated should not be used in high-rise buildings.
So, in answer to the questions, laminated glass is not a combustible material, but is currently classed as one in the regulations.