The vapour permeable membrane has undergone rigorous testing with BRE to show that it can be used in all UK regions when laps are sealed.
The addition of integral sealing tapes intends to greatly increase the ease and speed of installation, whilst reducing the combined cost of underlay and tape in comparison to purchasing them separately.
The new minimum performance requirements included in the British Standard have been developed to determine the wind resistance of unsupported underlay.
They provide a region by region wind zone table that can be used to determine an underlay’s suitability for a given wind zone and batten gauge.
The upgraded Sandtoft VPM Classic has been added to Sandtoft’s range of underlays and roofing accessories, which also includes Sandtoft VPM Super.
Both products can be used nationally with all concrete and clay roof tiles and slates, and are suitable for both warm and cold roof designs on any roof shape and building.
A zonal classification will now be included on the VPM Classic and Super wrapping labels, to assist the installer with information on geographical zone suitability and maximum recommended batten spacings.