TIMBER & TIMBERFRAME
NEW HIGHER SPECIFICATION FOR DECK SUBSTRUCTURES
The specification
requirements for pressure
treated softwood deck
substructures are set to
change in BS8417, the
British Standard for wood
preservation, when it is next
revised with leading trade
bodies incorporating the
changes now.
This means that all softwood beams, joists, wall plates, blocking
and bracing will have to be pressure treated to the same level
as posts that are in permanent contact with the ground, a
category referred to as Use Class 4.
This brings the UK into line with standards in Sweden, Finland,
France and north America where the whole deck substructure
system (posts, beams and joists) is recognised as safety
critical.
TDCA members are working to adopt this change in policy in
readiness for the publication of the revised BS8417, probably in
2021. Leading the way, Use Class 4 joists are already available
from TCDA members Hoppings Softwoods, Silva Timber and
Champion Timber.
The question is how many decking installers will pick up on
this new requirement and ensure that the work they undertake
meets the latest standards? Certainly, TDCA DeckMark
accredited installers whose work is inspected to ensure
compliance, will be fully conversant.
To find a DeckMark accredited installer or enquire about
achieving accreditation, email [email protected] or visit
the TDCA website www.tdca.org.uk where you’ll find a UK
supplier search facility.
ARCHETECH - PAGE 84