IKO Undertile Felt is the traditional underslating, complying to British Standards and still favoured by many roofers. IKO Undertile Felt Reinforced slaters' felts are manufactured specifically for use as an underslating beneath tiles or slates in open rafter construction. It can also be used as a vapour retarder in built-up roofing. IKO Undertile Felt has a felt fibre base combined with a layer of open weave hessian, saturated and coated with bitumen and surfaced with sand. Features and Benefits Long established and highly regarded slaters felt Suitable for cold ventilated roofs UK manufactured To be used with IKO Eaves Protection Strip (Formerly BS747 Type 1F)