How deep should the terrace roof be because of rain?

Hello.
We are currently considering how deep the terrace roof should be so that we can still sit outside in the summer when a shower comes.
In the show home park, we saw 1.50m deep recesses in the house. That did not feel sufficient to us.
We will also have such a recess in the house. Do you perhaps have experience on how deep this recess, meaning the roof, should be to be able to "withstand" a shower?

we have a good 3m depth and even that is sometimes quite little. one should consider that the rain splashes back and forth on the ground and you could still get wet. it also depends on where the wind is coming from. 1.5m is definitely too little. when planning, be sure to observe the building regulations. permit-free terrace roofs are subject to different conditions depending on the federal state (usually max 30m², 3 meters depth). with a permit, of course, much more is possible, especially in terms of depth. 5x5m is easily feasible...

With a 3 m cut into the house, to be safe from rain if necessary, you will quite certainly also take away some sun in the living space behind it. I would consider the rain protection as a nice gimmick if it works out that way – but don’t try to base the volume of the house solely on that.

We have a setback of 1.50m. You can't sit outside there when it rains. But it is still ideal and a good compromise. In summer, you can sit somewhat protected from wind and sun, things can be placed outside and stay dry, in winter a few plants stand "im Trockenen" and the light incidence is not very limited.

I would probably completely avoid this cutout and build a separate roof...ours is about 5m wide x 4m deep and even there you get some rain from the side...table is placed in the middle 0.90x1.60m...with 6 chairs around it.

I already thought so. I would have also tended towards 3-3.50m. And what do you think about a combination of a cut of 1.50m and an additional massive light-proof roofing (concrete roofing) of 1.50m? Since our house is being built as a two-story with a flat roof, I could also imagine that visually well. The orientation would be south. I might have concerns about too little brightness in the adjacent living room. But maybe you can put my concerns aside...