ᐅ Which roofing material is best for a flat shed roof?

And how is the construction, with bitumen or without?

Hello,
no, we do not have a photovoltaic system installed on it. However, it would be easily possible.
I have attached a photo for you.

We are planning a pitched roof with a 10-degree slope and, if possible, waterproof with tiles.

I know that roofing tiles are generally not recommended for slopes under 12 degrees, but Bramac and Braas are not exactly "no-name" brands on the market:

There are roofing guidelines for this. Normally, trapezoidal sheet metal, fiber cement corrugated sheets, or standing seam zinc roofing are suitable up to 7° (5°). Possibly with double seams or similar techniques. Depending on the requirements, the roofing may need a waterproof underlayment with sealed counter battens. Specially designed roof tiles (Braas) are reportedly capable of providing durable coverage between 12° and 7°, but whether this makes sense functionally or aesthetically is questionable. A pure waterproofing layer using roofing membranes is generally possible but should be ventilated and must either be officially approved as a "soft roofing" system for the specific site conditions (bitumen membranes), have a gravel ballast layer of at least 5cm (2 inches), or be a plastic/elastomeric membrane with building authority approval that meets fire protection requirements. The choice of material is initially determined by structural considerations, then by design, and finally by price. Roof tiles and trapezoidal sheet metal roofing are roughly similar in cost, including all additional work. Fiber cement roofing is about one-third more expensive, while zinc roofing can cost two to three times as much, depending on the roof shape.

Maybe I should ask the question differently. Here is the construction description regarding our 10-degree pitched roof:

“A full-surface, rough-sawn wooden boarding, 24 mm (1 inch) thick, is nailed onto the rafters. On top of this, the waterproofing is applied with the following layers: A base layer of overlapping bitumen is nailed on. Next, a bitumen membrane is installed, which is fully heat-welded. As the third layer, another bitumen membrane is applied, with a stone chipping surface on the upper side. (Colors according to the sample template).”

My question is whether and how I can combine this with roof tiles? The roof tiles would primarily serve an aesthetic purpose (roof facing the street).

@Jochen104: What experiences have you had so far?