Which roofing material is suitable for a flat shed roof?

And how is the structure, with bitumen, or without?

Hello, no, we do not have a photovoltaic system on it. But that would be easily possible. I have attached the picture for you.

We are planning PD with 10 degrees and, if possible, waterproof + tiles.

I know, no roof tiles under 12 degrees, but Bramac and Braas are not "no name" players on the market:

link removed by moderation; Bauexperte

There are roofing guidelines for this. Usually, trapezoidal sheet metal, corrugated fiber cement, or zinc standing seam covering is used up to 7° (5°). Possibly with double seams, etc. Depending on the requirements, the covering may need a waterproof underlay with sealed counter-battens. With specially developed roof tiles (Braas), supposedly durable coverings between 12° and 7° are also possible. Whether that really makes sense and looks good remains questionable. A pure sealing with roofing membranes is generally also possible, but should be ventilated and must either be approved as a "soft roofing" by building regulations in the respective property situation (bitumen membranes), have a gravel load of at least 5cm, or as a plastic/elastomer sealing membrane with building authority approval meet fire protection requirements. The choice of a specific material is therefore initially determined by construction, then design, and lastly by price. A tile covering and trapezoidal sheet metal are quite similar in price including all additional work. Fiber cement is about 1/3 more expensive, zinc covering about 2 to 3 times the price, depending on the roof shape.

Maybe I should ask the question differently. This is the construction description regarding our 10-degree PD:

"A full-surface, rough-sawn wood sheathing, 24 mm thick, is nailed onto the rafters. The waterproofing is done with the following setup: a leveling layer of bitumen is nailed overlapping. Then a bitumen torch-on membrane is laid, which is fully welded on. As the third layer, another torch-on membrane is laid, which is surfaced with slate on the top side. (Colors according to sample template)."

The question is whether and how I can combine this with roof tiles? Roof tiles should, from my point of view, only play an aesthetic role (roof facing the street).

: What experiences have you had now?