Abstract: A sub-roofing element for a flat, plate-shaped structural element, in particular for a solar energy collection module that can be fastened to joist elements that can be laid on a pitched roof in the ridge-eaves direction, whereby the sub-roofing element is made of watertight material and has at least one water channel.

Abstract: A solar energy collection system for a pitched roof covered with roofing plates, with support elements that can be laid in the ridge-eaves direction. The support elements can be laid overlapping one another in the ridge-eaves direction, whereby plate-shaped modules having cells are located on the joist elements butted up against one another or adjacent to neighboring roof covering plates. The length of which modules can be greater than the greatest coverage length of a roofing plate, and the width of which can be greater than the system coverage width of the roofing plate.

Abstract: A joist element for fastening a flat, plate-shaped structural element to a pitched roof. In particular for fastening a solar energy collection module, whereby the joist element, laid in the ridge-eaves direction, can be fastened to the roof substructure.