December 2022

Fire Performance
KEEPING WATCH ON FIRE
STANDARDS
As pressures to find alternative products from outside the UK might mean turning to
products that do not meet the standards expected, Ben Midwinter, Technical Director at
Flex-R, advises to always check product fire test certifications…
The current climate of supply chain
challenges in logistics and production has
resulted in many tried, tested, and relied
upon products becoming short stocked. In an
effort to keep contractors moving, some suppliers
have sought out alternative manufacturers, often
from outside the UK.
While this may appear good news, the problem is
that not all imported flat roof coverings are tested
to the same level which can result in
underperformance in a fire.
Between changes in regulation and discrepancies
in fire performance, this has placed a heightened
focus on checking certification. For contractors, it
is vital to ensure any imported roof covering has
been tested appropriately and its performance is
legally compliant and acceptable for use in the
UK. Failure to do so risks the safety of the
installation.
Why aren’t all fire performance tests
equal?
The test methods used vary across Europe in
order to meet the requirements of each country’s
specific legislation.
Approved Document B (AD B) provides clear
guidance relating to fire safety in buildings. The
2019 edition of A DB included some major
updates to Requirement B4 which relates to the
classification of a flat roof system when exposed
to fire from an external source.
This piece of regulation is critical as it includes
changes to the fire testing methodology.
According to DD CEN/TS 1187:2012 there are
four test methods in response to the legislation in
“The problem
is that not
all imported
flat roof
coverings
are tested to
the same level
which can result
in underperformance
in a fire”
place within different EU countries: t1 for
Germany, t2 for Scandinavia, t3 for France, and
t4 for the UK.
The test methods vary as such: test t1 is with
burning brands, and for t2 it is with burning
brands and wind. For t3 it is with burning
brands, wind, and supplementary radiant heat.
T4 is a two-stage evaluation of the fire
performance of a roof with burning brands, wind,
and radiant heat.
T4 tests external fire spread and penetration by
fire. It is also the only test method that complies
with the requirements of the Building Regulations
and legislation for roof coverings used in the UK.
Therefore, suppliers and contractors need to
check that imported roof coverings have been
tested using Test 4.
Contractors should be on the lookout for a roofing
system classified as BROOF(t4). Test results are
given as European class ratings, using the
standard BS EN 13501-5 and are in five different
ratings. The highest, and the class rating used for
Ben Midwinter says BROOF(t4) is the gold
standard for the UK when it comes to the
performance of flat roofs and fire.
the UK is BROOF(t4), with the
lowest being FROOF(t4).
Why are the differences so
important?
The classifications are vital because
they dictate the minimum distances a roof
covering can be used from the site boundary,
depending on the building type and its use.
BROOF(t4) is the gold standard for the UK when
it comes to the performance of flat roofs and
fire; it means an EPDM roof covering, for
example, can be used on roofs without
restriction.
On the other hand, a roof covering with an
FROOF(t4) classification can only be used on
roofs over 20m from the boundary.
The Grenfell tragedy means there is now a
greater understanding of how small changes to
material specifications can have a significant
impact on fire safety. Therefore, roofing
contractors need to be vigilant in ensuring the
products used have the appropriate
certification for use in the UK to ensure the
safety of building users. It is the duty of
manufacturers and distributors to make this
information readily available.
Contact Flex-R
www.flex-r.co.uk
01494 448792
@FlexR_UK
38 TC DECEMBER 2022