Roof slope and types of roof supporting structure
According to the ITB recommendation, corrugated bitumen sheets can be used for roofing with an inclination of not more than 20 °. (44%). Depending on the angle of the roof, an appropriate substructure structure should be used to properly support the corrugated sheets of the roofing..
For smaller roof slopes, solid formwork or waterproof wood-based panels or plywood should be used as a base for the roofing.. In the case of a greater inclination of these slopes, the undercoat is made of wooden years spaced apart 45 or 60 cm on the rafters of the roof. On the other hand, the panel joints in the seams parallel to the eaves should have an overlap of min. 17 cm, and the panel joints in the seams perpendicular to the eaves are made in one wave. The dimensions of the cross-section of the years under the cover depend on the spacing of the rafters. It follows from practice, that with the spacing of the rafters to 100 cm, the cross-section of the battens should be 4×6 cm, and for rafter spacing from 100 do 125 cm, it is 6×6 cm. For larger spacings, the batten cross-section needed should be selected according to static and strength calculations.