BW Industries - Tiled / Mansard Roof

These types of roof covering may cause bending about both axes of the roof purlins due to their weight. In order to provide adequate restraint rigid struts should be used in lieu of anti sag ties. The ridge purlins should be tied using a rigid apex strut. Diagonal bracing wires are required between the top two purlins. Additional diagonal bracing will be required for every 6m length of roof slope. The struts should be arranged such that the maximum unrestrained purlin length is restricted to 2m. The timber rafters should be joined across the apex or be fixed to a ridge board.