The "Technical Rule for Roofing with Roof Tiles and Roof Tiles" (ZVDH) describes which additional measures must be taken if the standard roof pitch is not reached. Increased requirements due to use, construction, climatic conditions and technical facilities are taken into account and a statement is made as to how many degrees the standard roof pitch may be undercut. In no case may a minimum gradient of 10° be undercut, provided that this is at all possible in the specific case, taking into account all influencing factors. In addition, manufacturers also specify their own minimum roof pitches for their products.
Source: bauwion
