Shed roof or rather hip roof for a bungalow?

I have read it (not yet seen or tried it, but just google "Walmdach alle Seiten belegen" in image search). What seems doubtful to you about it?

From my study, I can see the roof of our neighbor (flat-roof bungalow, built around 1980), where water always stands on the roof. Even when it has been dry for 2 days.

That's why I don't want a flat roof, but a shed roof so that water can NEVER accumulate on the roof in the first place! And regarding 1980: It was the same with my parents' house from the 80s. But now it's the year 2021. Hence my question about a shed roof.

A shed roof is nothing other than a flat roof, just with a slightly angled roof so that the water drains better.

No, the shed roof is the single-sloped version of the gable roof: beyond the ridge, it does not slope down again to a second eave. Theoretically, if you have too much money, you can also hip a shed roof.

Regarding photovoltaics, the yields for the respective location and orientation can be calculated with PVGIS. For installation itself, a hip roof is of course the least favorable due to the shape (modules square, roof section triangular or trapezoidal). Additionally, it probably requires separate strings etc. for each side.

With otherwise the same inclination, I suggest that a shed roof has a flat surface evenly covered or similar, thus fewer transitions, corners, or edges. Whether this is really significant in practice is another matter. If it is only about susceptibility, the angle will probably have more influence than one edge more or less, provided the work is done properly. We moved from the initial design with 12° according to the architect to 20° because it is clearly simpler and cheaper, as for example no tight under-roof and extra securing of the tiles is necessary. The rest is mainly a matter of taste and "permission" or depends on the purpose of the overall architecture.

So I would build exactly what I like best or where my priorities are most likely met. A different roof also offers different possibilities for interior design, so I would rather base it on that. A flat roof today is just as watertight as a pitched roof if it is properly executed. With the old flat-roofed bungalows from the 70s-80s, that may have happened occasionally, but I was already a guest in such buildings back then and never had wet feet. Problems can still arise everywhere during construction today, whether with the installation of windows, skylights, connections, joints, thermal bridges, poor ventilation, and much more. Have a look, for example, at the company BAUDER or similar; they build functioning flat roofs everywhere with the latest materials, so I believe this is rather a concern that still lingers among the older generation. Due to concerns about watertightness, I definitely would not choose a roof other than the one I want. In every house today, you find a walk-in shower with a tiled floor, something that would hardly have been imaginable in the past.

But we are now in the year 2021. Hence my question about a monopitch roof

And a monopitch roof has exactly 0 difference compared to a hip roof with the same roof pitch. At least when it comes to the issue of tightness.

(It’s like the question whether you can drive 200 with a red or better with a blue car)