How many rest bends and turns can soil and vent system have?

[birdinbeard]

I currently have one ground floor wc at back of house in bathroom. 110mm wc waste goes straight out through external wall in to branch with bath, sink and shower into it too. No stack, just capped branch at ground level. Then waste runs down 800mm into 90° rest bend and away to sewer.

I am moving bathroom above the existing. Keeping a wc on ground floor but moving across the room. The new 1st floor wc soil comes out of the external wall not directly in line with existing underground soil pipe and being lazy AND busy I want to have the new soil stack in line with the 1st floor wc soil exit, which is about 3' to the right of the existing set up.

Can I put in a rest bend at the bottom of the stack, leading over and conecting to a tripple branch bang on to of the vertical underground soil pipe that is already there. Waste will need to drop through 2 rest bends.

A; will this work?
B; will BC pass it?

I think I have attached images??!!


Thanks

proposed soil setup

• birdinbeard
• 6 Jan 2013
• 1

 

[Homesafe]

You have done the hard work of digging up the ground so know get aninspection chamber in, it will not only connect the two wc's correctly it will be right for any future blockage .
Although the way you have shown will/ should be ok.

 

[Nige F]

A; will this work?
B; will BC pass it?

I think I have attached images??!!


]

A Yes B NO

 

[SandyLyon]

You should use an inspection chamber in any of the following situations, at the head of the drain, at any change in direction or gradient, at all junctions, at all changes in pipe dia. There may be others that I have forgotten.
In some of these situations you can use a rodding eye instead, I would suggest looking at the reg's and downloading some installation instructions from a manufacturers web site (Wavin,Polypipe, Marley)

 

[birdinbeard]

Hi Nige F. Can you say why BC would not pass this? Too many turns / bends?? Thanks.

A; will this work?
B; will BC pass it?

I think I have attached images??!!


]

A Yes B NO

 

[doitall]

No vent pipe.

 

[birdinbeard]

SandyLyon; Inspection chambers look a bit large. I am trying to minimise digging. I see the benefit of having the ability to rod the system so would I be able to do this by using a Screwed access cap on the 3rd / top connector on the tripple branch?

 

[doitall]

No you must have a chamber.

 

[Hugh Jaleak]

Mini chamber should suffice, 250 or 300mm diameter, provided drain is no more than 600mm deep.

 

[Gasguru]

Just get BC round to have a look. I've had them ignore the regs and use "engineering judgement" and common sense. Can save a whole lot of digging.

Can you not run the new stack into the top of the existing junction (with and offset)?

 

[birdinbeard]

I'm sorry I did not mention there is an inspection chamber about 3 meters from the existing branch which then goes to the main sewer. With this in mind will the 2 x rest bends be acceptable with the top of the new underground tripple branch capped with a screwed cap? Thanks for previous replies I thought that the advice given about having an inspection chamber was suggesting I needed one at the base of the stack.

 

[Hugh Jaleak]

BCO is unlikely to allow what you propose in the diagram, but no harm in asking. It's generally frowned upon having any bends in the wet part of the stack between the soil branch and rest bend at the base of the stack going into the drain.

If your idea isnt acceptable I would expect they'll either insist on a mini chamber on the end of the current run against the wall, with the new connections coming in either side, or take the new stack up from current drain position, connect new ground floor WC on one junction, and 1st floor on another junction at the appropriate levels.

 

[birdinbeard]

Thanks Hugh Jaleak and everyone else who has advised etc. Bristol BCO visited today and OK'd my plan which is great - not so much digging now javascript:emoticon('') . HOWEVER... javascript:emoticon('')Because I'm running the underground soil pipe along the base of the wall to the existing branch I am going to have to cut away some protruding edges of foundation wall. SDS time javascript:emoticon('')

 

[Nige F]

You wouldn`t have got away with it in Sussex.