ᐅ Is a gutter necessary below a terrace window?

Hello,

I am currently planning the construction of our terrace. We want to build the terrace flush with the three floor-to-ceiling window units.
Recently, I walked through a new residential area to see how other builders have handled this.
Many have no drainage at all, some only have drainage directly at the masonry (basically between the windows), and others have it right below the windows.
In the red-marked areas, there would be space for a gutter. The two outer ones could be drained directly into the downspouts.
Does that make sense? Would a water trap be necessary for rainwater if the water is temporarily stored in a cistern?

I am looking forward to your ideas, thank you in advance.

Best regards
Julian

What does your architect or landscape designer say about this? They have to ensure it is properly handled if necessary.

We checked again with our construction company about this. In principle, windows with a flat threshold apparently require a drainage system.

We have a roller layer made of facing bricks underneath, and the terrace is positioned below this roller layer. According to the builder, in this case, no drainage is needed. He said, "If the water is that high, we have much bigger problems" 😀

We have a ground-level entrance, so it would make sense to install a drainage channel. The architect is no longer available since the construction has been completed and he has since retired. The landscaper said it’s not necessary, although I would prefer to be on the safe side.

What has been your experience with connecting a drainage channel to the rainwater system when a cistern is involved (regarding odor issues)?

julianpe schrieb:

Many have no drainage at all, some only have a drain directly on the wall (basically between the windows), and others again have it right below the windows.
In the red-marked areas, there would be space for a gutter. The two outer ones I could drain directly into the downspouts.

The question is what kind of terrace you want. For a stone terrace with a ground-level exit = yes, install a drainage channel. For a wooden terrace/WPC decking = no, do not install a drainage channel (however, this does not comply with regulations and is a pragmatic and well-functioning solution).