Shower plumbing advice

[geoff@gandaconsultin]

I am having an en-suite shower replaced, with the existing toilet to remain. The old shower outlet went outside (above the garage) and into the same large pipe that the toilet goes to. The guy doing the work wants to run a separate outlet pipe past that (the disconnected one laying next to the toilet outlet) and into the vertical drain that the main pipe is connected to., bypassing the big pipe altogether. I'm not sure what the large vertical pipe does (some sort of vent?) but I suspect all the waste water should go through the original big pipe. I'm also wondering if doing what he wants to do is against building regs. I hope that all makes sense,

 

[terryplumb]

Your post Makes no sense to me I am afraid.
Is that small white pipe laying on the roof the disconnected shower waste ? If it is ,show us where it was connected to the 4 inch pipe. And show us where the new shower waste is proposed to connect.

 

[geoff@gandaconsultin]

Yea, sorry, I thought it was a bit cryptic. Hopefully these 2 photos with comments will help explain. I think he intends extending that new pipe a bit further and then going through the wall below where the 4" pipe goes. God only knows how he thinks he's going to connect it. Can't see it working somehow. The black pipe is just a rainwater downpipe that runs down the wall, across the garage roof and into the garage gutter.

 

[terryplumb]

Is the existing hole in the wall where the new shower waste pipe is going to come out ? If it is ,I can't see why it can't connect directly into the horizontal end of the soil pipe. And I have no idea why he wants to run it what appears to be several metres ,not to mention how he can do it and retain a fall on the shower waste pipe

 

[geoff@gandaconsultin]

The hole is where the old pipe came out. The old shower was higher up than the new one so obviously the new one is lower (he ran it under the floor). The new one is to the left of the photo so you can't see it. The new one should just connect where the old one was (to the 4" pipe) and I have a horrible suspicion that there's not enough fall on that either. What is the tall vertical 4" pipe just to the right of the soil pipe?

 

[polesapart]

I suspect all the waste water should go through the original big pipe

So do I.

I'm also wondering if doing what he wants to do is against building regs.

Almost certainly, unless your house has combined (rainwater+foul)drainage

I fear your man has c*cked it up. Lack of planning. Rule 2 violation.









Plumbing rule 2: sh*t doesn't flow uphill.

The first thing you do on a job like this is plan your waste runs with regard to minimising lengths, changes of direction etc. but above all keeping the correct slope on your waste pipework.

 

[terryplumb]

The hole is where the old pipe came out. The old shower was higher up than the new one so obviously the new one is lower (he ran it under the floor). The new one is to the left of the photo so you can't see it. The new one should just connect where the old one was (to the 4" pipe) and I have a horrible suspicion that there's not enough fall on that either. What is the tall vertical 4" pipe just to the right of the soil pipe?

Where is the new pipe coming out ?
The vertical part is the vent

 

[JonathanM]

Deleted post. Not needed now.

 

[geoff@gandaconsultin]

So do I.

Almost certainly, unless your house has combined (rainwater+foul)drainage

I fear your man has c*cked it up. Lack of planning. Rule 2 violation.









Plumbing rule 2: sh*t doesn't flow uphill.

The first thing you do on a job like this is plan your waste runs with regard to minimising lengths, changes of direction etc. but above all keeping the correct slope on your waste pipework.

It doesn't, and he clearly has. This is going to get messy.

 

[geoff@gandaconsultin]

I can't tell for sure from my photo but I suspect there is a (very) slight fall on the new pipe. Is it possible to get some sort of adjustable/bendy adapter that would connect the new shower waste to the 4" soil pipe?

 

[terryplumb]

Yes ,flexible pipes are available. Better with rigid pipe ,which can be heated and bent a bit.

 

[Hugh Jaleak]

Looks like a total Cowboy job, sorry to say. My understanding is, that is the new shower waste running across the garage roof, the whote waste pipe?

Firstly, the length looks to exceed the permissible 3metre max run in 40mm, secondly, it's got more dips than a Restaurant, and thirdly, has he coupled it into the rainwater pipe?

Problem now is, if the new shower waste arrangement is too low to be able to connect to the soil pipe, then your options suddenly become very limited (Or expensive.) May be possible to upgrade to 50mm waste after 3m, and run that to the vertical stack, but again, that depends on distance to stack, and also looks like it may have to go through the wall immediately above the flat roof, which may cause issues in itself.

 

[Harry Bloomfield]

Unless you have a combined waste system, it is illegal to discharge grey water (from the shower) into the rainwater drainage system. If that is the case, then you need to stop him right now, before he continues.

 

[geoff@gandaconsultin]

Unless you have a combined waste system, it is illegal to discharge grey water (from the shower) into the rainwater drainage system. If that is the case, then you need to stop him right now, before he continues.

Yea, I've already put a stop to that.

 

[geoff@gandaconsultin]

I'm hoping there is fall on it and he can get it connected where it's supposed to be. As said, the alternatives are pretty bad. He assured me many times that it would drain correctly so it's on him, but I'm still the one losing sleep. He's back tomorrow so we'll be having a "full and frank discussion".

Thanks to all for your replies and advice, very helpful even if it's not what I wanted to hear.