ABSTRACT
A roof is classified as flat if the pitch/fall does not exceed 10°. Flat roofs are classified as either: cold deck, warm deck or inverted warm deck according to where the insulation is in the construction. The traditional method of providing a waterproof covering for flat roofs with a timber structure is built up felt roofing. Underlay is placed over plywood or a similar smooth surface decking, or over rigid insulation boards. Single ply membranes are durable, resilient, flexible and lightweight sheet materials composed mainly of synthetic polymers. Some are reinforced with glass fibres depending on application and coverage area. Application is mainly on flat roofs, being a composite structure of insulation, drainage layers soils and vegetation to create an environmentally and ecologically friendly building element. A substantial building structure is required for support and it is only feasible to use a flat roof.
