Adding to drainage

[bsr]

Hi, in the picture you can see I have a channel drain (black 40mm) which then goes through a 135 bend into the white pipe, which goes into the gully via a strap boss. I need to add a second channel drain (also a 40mm outlet). The 40mm pipe gets overwhelmed so I need to increase capacity.

I am thinking of the following and would like your advice:
1. Replace the gully top with a double socket tee like this.
2. Replace the white 40mm with 110mm.
3. Replace the 40mm 135 with either a 110mm 135 tee or with a mini inspection chamber and add in the new drainage.

Thoughts please? My main concern is that I may not have enough fall on the new double socket at the gully end, which means having to dig out and try to lower the whole gully?

 

[23vc]

Deffo on the right lines, 110mm and lose all the 40mm. Not sure on gulley height but it’s one of those things that become easier when you dig out and expose it and try it

 

[noseall]

Hi, in the picture you can see I have a channel drain (black 40mm) which then goes through a 135 bend into the white pipe, which goes into the gully via a strap boss. I need to add a second channel drain (also a 40mm outlet). The 40mm pipe gets overwhelmed so I need to increase capacity.

I am thinking of the following and would like your advice:
1. Replace the gully top with a double socket tee like this.
2. Replace the white 40mm with 110mm.
3. Replace the 40mm 135 with either a 110mm 135 tee or with a mini inspection chamber and add in the new drainage.

Thoughts please? My main concern is that I may not have enough fall on the new double socket at the gully end, which means having to dig out and try to lower the whole gully?

View attachment 357308

Add another gully. Try and get rid of those 40mm runs and get the waste into a gully as quickly as possible. They can sludge up very quickly.

 

[bsr]

Thanks @noseall where should I add the extra gulley? Where I've suggested putting an inspection chamber? In which case how do I join the two inlets at 45 degrees?

 

[Hugh Jaleak]

I would suggest looking at removing the existing arrangement and replacing some of what is currently below ground. Putting the junction into the top of the Gully trap, (where the boss is located now), may give you chance to get enough fall on the 110mm pipework across to your proposed new Gully position, but ideally you want to do away with all the 40mm below ground if possible.

If the black 40mm must remain then look at dropping that into a 45º junction immediately before the new Gully.