Onduline has produced a new brochure for its Ondutile roof underlay system. It provides detailed specifications and fixing instructions for the construction of low-pitched roofs using all types of tiles and slates. It also covers the application of the Ondutile system to insulated pitched roofs. Ondutile provides a secondary weather-proof membrane and although primarily used to reduce the pitch of tiled and slate roofs it also improves the thermal and sound insulation properties of the roof. The system has BBA certification.