Replacement shower - waste pipe.

[RobinClay]

I'm replacing an old shower cubicle.

1.
The old waste pipe and the new trap outlet are separated by 540mm longitudinally (in line), but also offset by 30mm horizontally and 80mm vertically. I think these offsets are too small to allow for a left-and-right elbow. Suggestions, please ?

2.
The waste then runs straight through the brick wall that forms a wall of the shower, and then turns almost horizontal across the wall (below the loo soil pipe), picking up the basin waste before discharging into the soil pipe from the loo in the bathroom. (Yes, it's complicated!) Should this waste pipe be vented? Obviously, I want to do the absolute minimum !

Soil pipe stack.

• RobinClay
• 14 Aug 2014
• 1

Bathroom on the left; en-suite on the right (floor two steps higher)

Enlargement

• RobinClay
• 14 Aug 2014
• 1

Bathroom on the left; en-suite on the right (floor two steps higher)

(Click on pic to enlarge it)

En-suite waste

• RobinClay
• 14 Aug 2014
• 1

Shower waste on the right; basin waste joins at the T

 

[Hugh Jaleak]

Unlikely you'd need to vent the pipe, but I would try and reconfigure things to avoid the two elbows you mention. (If need be put another hole through the external wall and reconnect outside.) Putting a dogleg in is asking for trouble and may make it impossible to get a 'snake' along the pipe to clear any future blockage......

 

[RobinClay]

Thank you for your response. Nice to have a 2nd opinion on venting the pipe ! The trouble is, it's all solvent welded, and flat (but sags a little). Also it would probably need a scaffold - AND it's on my neighbour's land !

... avoid the two elbows you mention. (If need be put another hole through the external wall and reconnect outside.) Putting a dogleg in is asking for trouble and may make it impossible to get a 'snake' along the pipe to clear any future blockage......

I don't think two elbows would fit anyway. Would it be possible / practicable to warm the 540mm length of plastic pipe enough to soften it so I can put a gentle dog-leg in it ?

 

[sooey]

That waste pipe has got no fall, no brackets, It's been teed into the wrong part of your neighbours soil pipe wrongly, posssibly causing an obstruction in his pipe.
I'd be thinking about redoing it, you wouldn't need a scaffold.

 

[RobinClay]

That waste pipe has got no fall, no brackets,

Agreed, no fall. However, it is supported by the connection from the basin waste, see the bottom pic above.

It's been teed into the wrong part of your neighbours soil pipe wrongly, posssibly causing an obstruction in his pipe.
I'd be thinking about redoing it, you wouldn't need a scaffold.

Well, quite. Ideally I would like to re-do the whole lot; it really is an eyesore. However, I think it's TFD at the moment - and it does work. "if it ain't broke..." I have other priorities - like getting Her Majesty's en-suite working again ! It's a basin & shower waste, so "shouldn't" get blocked. It ought, of course, to have, on the right hand end, not the elbow, but a Tee with a rodding eye.

It's actually our bathroom on the left; it's a gable wall, which is our property boundary, so any access is on our neighbour's land. It's his view (but only from his drive), and he hasn't complained!

Thanks for your response. Still have the challenge of connecting new trap to old waste pipe....

 

[Hugh Jaleak]

Warming and bending plastic waste pipe was something we tried at college, (with limited success!), and required the use of a proprietary former, inserted into the section to be bent to prevent the pipe distorting. I think in your case even if such a former was available, the pipe will have hardened with age and as such, become exceedingly brittle. Attempting to cut it may cause it to partially shatter or snap, attempting to bend it would be extremely ambitious I suspect!

In all honesty, I would be looking to bite the bullet and replace it. Leave basin as is if that works, although wouldn't do any harm to fit a rodding eye to cap off the current run to the shower, then fit a new run to suit new shower position. I appreciate it's work you could do without at present, but I would suspect the last thing you want is a nice new shower that wont drain properly due to a badly installed waste! (And a bent ear!)

 

[longdogs]

I have warmed and bent plastic waste pipe in the past but only a few degrees - when a 135deg is too much.