Fixing a combined rainwater into soil stack issue

bpgreen1

After a recent extension was built, a new rainwater downpipe was routed into the soil stack when it was also resited to the outside of the house.
When the buildings control guy came round to take a look he said that the soil stack can now effectively shortcut going up to the roofline, and can now vent from only 7ft (the height of the new gutter off the extension). See image below... (might explain better)

I think I need to separate the two again, and put the rainwater through a bottle trap, or similar, and after that into the waste pipes. But is there such a thing to do it above ground inline, or am I going to have to dig down to bury a trap and get the rainwater to the drains that way?

Any advice appreciated... thank you!
Baz

(cant post images because its my first newbie post! So here is the hard-url instead)

tinypic.com/r/vhff2w/6

blackshirtuk

bpgreen1 wrote: »

I think I need to separate the two again, and put the rainwater through a bottle trap, or similar, and after that into the waste pipes. But is there such a thing to do it above ground inline, or am I going to have to dig down to bury a trap and get the rainwater to the drains that way?

I see the problem and yes you would have to put a trap below ground level. Is that what building control have asked you to do? I would ask them what they would like you to do. Saves doing it twice!

Normally rainwater would be dispersed into a soakaway not the soil drain.

bpgreen1

Thanks for the prompt response.
The inspector simply said it couldnt be routed as it is currently - maybe he assumed I'd know that it had to be below ground. I'll double check with him to confirm - good point...

And yes, it is fine to not go into soakaway, it was on original plans to do it this way.

keystone

BC guy is correct. Wheres that vertical that the gutter pipe joins going?

It should be below ground level and look something like this:



You can run surface water into the foul sewer. What you shouldn't do do is run waste water into a surface water sewer.

Cheers