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Kooltherm K21 N Rainscreen Board is a phenolic foam insulation board with a fiber-free core. It has a permeable mineral coated glass tissue facer on the back and a black expandable graphite, glass tissue complex facer on the front side. This facer expands when in touch with fire and creates a protective layer to help limit the spread of the fire. The board is vapor diffusion open, meaning it can help to significantly reduces the build-up of water vapor in the construction.
Product Highlights
Reaction to fire (EN 13501-1): B-s1,d0
λD-value 0,021 W/(m·K)
Vapor diffusion open
Expandable facer creates a protective layer to help limit the spread of the fire
Ideal for ventilated facades with an open structure, due to the black facer