CEILINGS, INTERNAL WALLS & PARTITIONS
When designing a building, it is
Knauf AMF commercial director, Peter Symons, discusses how acoustic
essential to understand how the
ceiling systems can help an interior structure achieve the best fi re
various elements of the structure
perform during a fi re.
resistance performance. Suspended ceiling systems, being a large
uninterrupted surface in a space, play a vital role
in fi re safety. The term fi re resistance is often
used but there are many interpretations of what
this actually means. Ultimately the industry
must follow the guidance of the current Building
Regulations. We hope the following interpretation
brings some clarity.
Building Regulations Approved Document
B; Section B2, Internal Fire Spread (Linings),
dictates the required properties of a material
BUILDING PRODUCTS | SEPTEMBER 8
and the ability of its surface to resist the effects
of fl ame and heat, thus reducing or eliminating
its contribution to the growth of a fi re in a given
space. This is termed ‘fi re reaction’.
Classifi cations are currently determined
by testing to the Euroclass standards in
accordance with BS EN 13501. These decide the
combustibility, ignitability, fl ame spread, calorifi c
value and the development of smoke and burning
droplets of a material returning a classifi cation
of A1, A2, B, C, D, E and F. Class A1 and A2 is
deemed non-combustible but for classes A2-D
there are additional designations for smoke
development s1, s2 or s3, and the amount of
burning droplets produced d0, d1 or d3.
Historically, BS476: Parts 6 and 7 was the
norm with tested samples being classifi ed from
Class 0 (best performance) to Class 4. Class 0
is not a fi re test, rather a classifi cation from The
Building Regulations, Approved Document B.