TDUK SupplyingTimber Issue 8 DIGITAL - Magazine - Page 73
———— WOOD PROTECTION ————
FLAME-RETARDANT TREATMENTS
NEED BETTER UNDERSTANDING
he Wood
Protection
Association (WPA)
has released
a statement
reminding the industry about
the importance of specifying
the correct 昀氀ame-retardant
treatments after a report on
the Collaborative Reporting
for Safer Structures UK
(CROSS-UK) online platform
expressed concerns about
the behaviour of thermally
modi昀椀ed timber in 昀椀re and
昀氀ame retardant testing
certi昀椀cation.
The CROSS-UK Report ID:
1314 'Fires involving thermally
modi昀椀ed wood' highlights
the behaviour of thermally
modi昀椀ed timber in 昀椀re, citing
two incidents where 昀椀res
spread over the external face
T
of buildings where thermally
modi昀椀ed wood was said to be
present as a facade material.
One of these 昀椀res was in the
UK, the other in Turkey.
In the report, the reporter
expressed concerns that there
is a wide range of thermally
modi昀椀ed wood products with
very di昀昀erent 昀椀re performance
ratings, and called for greater
clarity regarding the testing,
speci昀椀cation, certi昀椀cation and
marketing of these products for
various uses.
Every CROSS-UK report
published is also commented
on by an expert panel which,
in this case, noted that "the
use of sustainable materials is
important, but that designers
should understand the various
factors that can a昀昀ect the
reaction to 昀椀re performance
of a wood-based external wall
system".
Responding to the report,
the WPA said 昀氀ame-retardant
treated wood for external use
should meet the requirements
of both a suitable reaction-to昀椀re classi昀椀cation report and
a durability of reaction-to-昀椀re
classi昀椀cation report.
Speci昀椀cally, the WPA
recommends that 昀氀ameretardant products are applied
under quality-controlled factory
conditions. This is to avoid the
quality issues that can arise
from these liquids being applied
on site, which the WPA does not
recommend.
Matthew Powell, Chair of
the WPA’s Flame Retardant
Committee, explains: “There
are many unknowns when
treating wood cladding with
About CROSS-UK
About WPA
Collaborative Reporting for Safer Structures UK
(CROSS-UK) provides free safety information for
the built environment. This is published based on
the reports on 昀椀re safety and structural safety
related to buildings and other structures in the built
environment it receives, as well as information in
the public domain. It is a con昀椀dential reporting
system which allows professionals working in the
built environment to report on 昀椀re and structural
safety issues. According to the organisation: “These
are then published anonymously to share lessons
learned, create positive change, and improve safety.”
The Wood Protection Association acts as a
technical and advisory body providing guidance
to the timber product supply chain, speci昀椀ers,
contractors, engineers and architects on the best
ways to ensure wood is 昀椀t for its intended purpose.
By promoting and developing technology that
enhances the performance and value of sustainable
softwood products – mainly through preservation,
wood modi昀椀cation or 昀氀ame-retardant treatment
– the WPA enables the timber industry to realise
wood's full potential. It is the leading UK body on all
matters concerning wood protection.
SUPPLYING TIMBER
73
SPRING 2025
TIMBER KNOWLEDGE
The Wood Protection Association is calling on timber cladding designers
to improve their knowledge about the speci昀椀cation of 昀氀ame-retardant
treatments, in response to the publication of a report on 昀椀res involving
thermally modi昀椀ed wood.
