• Water Vapour Resistance 0.20 MNs/g
• Superb water resistance 3.0m
• BBA certified – 04/4145
• Excellent nail and tear strength 105N when tested to MOAT 27:5:4:1
• Complies with BS5534
• No nuisance noise
• Good UV stability
• Easily identifiable bright blue colour
• Lap lines printed for easy installation
Vapour Permeable Roofing Underlay
MATERIAL
Harcon VPU has a 3 layer composite structure with the highly vapour permeable film bonded between two layers of nonwoven polypropylene.The top polypropylene layer provides high levels of water resistance while the bottom layer provides the strength for this flexible breather membrane which can be used in both unsupported and fully supported applications.
PRODUCT DETAILS
Thickness 0.5mm
Weight 0.125kg/m2
Width 1000 and 1500mm
Length 50m
Roll Weight 6.25kg and 9.38kg
Colour Bright Blue
PURPOSE
A vapour permeable membrane has 4 functions to perform.
1Condensation Control
It allows warm moist air generated in the building to pass freely through it, helping to prevent condensation in the roof. As it is waterproof the water drops created by the condensation which forms on the primary roof covering will simply roll down the Harcon VPU into the gutter.
2Secondary Roof Covering
Stops any rain or snow which penetrates the roof tiles or slates getting into the building below.
3Temporary waterproofing
During construction and if the primary roof covering is damaged Harcon VPU will protect the structure below.
4Wind
Harcon VPU will prevent wind and any particles it may be carrying entering the roof void.
