What should downpipes run into?

[Wonderbug81]

The downpipe is part of a shared property (house). I am looking out from my flat on the first floor. The downpipe water will run onto my neighbour's flat roof but if there's a lot of water, it looks like it could run onto my landing wall (right of the photo).

He says the felt has been run so as water won't run onto my wall. Should it not run along another downpipe off the roof?

No, that is normal. There will be a fall on the roof that will take the water across the roof to a lower gutter.

You mention a flat roof. I presume this is an extension or addition since the house, and the rainwater arrangements, were originally designed and built.

These are not always very good.

With luck the shoe on the end of the downpipe will gave been oriented to start the water flowing down the slope of the flat roof towards its gutter. The gutter on the extension needs to be big enough to take the volume of water. It probably has its own downpipe emptying into a gulley in the ground.

Thank you. Not sure about the roof, all the Victorian houses have this here. But the roof has just been redone. It's a flat roof as you say.

Maybe it's OK if the water is emptying into a gulley.

The flat roof has a very slight slope, so water coming out of that downpipe will run into the gutters at the edge of the roof. Ours is like this too it's fine.

It’s fine until the roof material disintegrates and then it’s not fine at all! This is a well known problem for flat roofs and far too many don’t have a fall on them. It’s much better to have a horizontal drainage pipe attached and that drains into the guttering. Flat roofs are not designed for drainage like this. Drain pipes are. If is likely to cause issues with the roof. It’s also a cheap solution because roofers cannot be bothered to add a pipe.

I hope you're joking?! 😬

@Wonderbug81 Er no! It’s obvious that extra water is being forced onto the roof. They are not designed for that. A pipe is a much better solution. Just because people say the roof should have a fall on it doesn’t mean the roof is designed to take an excessive flow of water and the lack of a pipe is poor. Roofs don’t last long without excess water on them. It’s never designed for this!

My last house was like that and I had no problems at all.
Reading the above posts though, maybe that was just luck!