Following on from NFRC issuing guidance regarding underlays and BS 5534:2014+A2 2018 in January 2019 and again in February 2020, information regarding meeting the full requirements of the standard is contained within the new roofing underlay manual from DuPont™ Tyvek®.
Derek Lewis, Technical Specialist at the DuPont™ Tyvek® Building Knowledge Centre commented: “It’s quite common to see underlays used in locations where the wind uplift requirements of BS 5534 are not met in full—this means that damage caused by wind uplift can be expected to occur whilst also incurring significant costs in call backs for the contractor.
“The use of a DuPont™ Tyvek® underlay, complete with its all zones, unrestricted BS 5534 certification means that contractors can use one material in applications that not only meets the code of practice for slating and tiling but also BS 5250, control of condensation in buildings, and thermal insulation requirements across the UK.”
DuPont™ Tyvek® underlays not only provide protection of buildings and occupants from the elements but also ensures that the building performs as designed, with the harmful effects of wind washing on thermal insulation drastically reduced.
Of course, this is backed up by BBA certification (DuPont™ Tyvek® was awarded the very first certificate for non-ventilated, thermally-efficient pitched roofs in 1999) for peace of mind for the specifier, contractor and building occupier.
For help and advice, please go to: www.building.dupont.co.uk
