Bison VCL is P-labeled and used on the warm side of the wall or roof structure. Bison VCL is used to seal air and to control the water vapor. Bison VCL works well with Bison House wrap in walls and Bison Permeable Roofing Underlay / Bison Permeable Roofing Underlay 175 for roofs.
The VCL is less open to diffusion compared to Bison House Wrap but more permeable than a classic air & vapor barrier. Thereby facilitating it for any construction moisture to dry out / exhale. With Bison VCL you build air tight but open to vapor, so that you do not seal in any moisture.
Bison Vapor Control Layer fits all houses where you want a more forgiving design that can breathe. The properties are especially suitable to for example vacation / seasonal housing where the heating occurs periodically.
Length: 25m & 12,5m (standard)
Width: 2,8m (standard)
Water vapor resistance: ca 140x10³ s/m,
(Compare to Bison House Wrap: <0,5 m, Bison Permeable Roofing Underlay: 0,11 m)
Tear strength: 195 N
Elongation: ca 50 %
Tensile strength: ca 200 N/5 cm
Water tightness: Tight at 200 mm (2kPa)
Bison Flex Tape, Butyl tape