Shower drain back flows... any solutions?

[kevster310]

Hi there,

Recently remodelled my bathroom and put in a new shower tray at floor-level... unfortunately this meant that it occasionally backflows if there's a lot of water draining from the kitchen sink/washer... etc. I live in a victorian mansion flat so the plumbing is about 30 years old!

I've tried putting drain cleaner down all my drains but it hasn't solved the issue.

Was wondering if there's anything else I can do that's not as drastic as tearing everything up again?

Thanks for the help!

 

[mountainman]

You could try fitting a non-return valve on the shower waste.

 

[kevster310]

thanks for the suggestion, is that possible to fit without taking the shower tray apart?

 

[mountainman]

thanks for the suggestion, is that possible to fit without taking the shower tray apart?

You need to fit it in an accessible section of the shower waste so only you can answer that question.

 

[vipey]

what about a hepvo ?

 

[PlumbBobBob]

what about a hepvo ?

that's what i would go for

 

[Simon F]

Recently remodelled my bathroom and put in a new shower tray at floor-level... unfortunately this meant that it occasionally backflows if there's a lot of water draining from the kitchen sink/washer... etc. Was wondering if there's anything else I can do that's not as drastic as tearing everything up again?

are all the waste pipes connected together? or are they independently connected to the stack pipe?
if the shower is teed into the same pipe as the sink it needs to be run independently to the stack
also what is the size and length of the shower waste pipe?

 

[kevster310]

Thanks for the message. I believe all the pipes are connected together. There's no way to check as everything has been walled up.

I posted a few pics of the drain here: http://www.ukplumbersforums.co.uk/p...er-shower-drain-advice-needed.html#post331173

It's 3 inches in diameter (on the inside) and 4-5 inches deep.

 

[Simon F]

( edited the question to make more sense. pipe not waste fitting size )
just trying to get to why there is a problem, understanding that will give the best solution
also what gradient fall is on the waste pipe?

 

[kevster310]

( edited the question to make more sense. pipe not waste fitting size )
just trying to get to why there is a problem, understanding that will give the best solution
also what gradient fall is on the waste pipe?

Sorry. Dont remember exactly what pipe was used but I think it was the same size as fitted on the sink so pretty standard?

The fall is very shallow, which is compounding the problem of course. The shower tray is essentially floor level.

 

[PlumbBobBob]

that could be your problem, the shower waste pipe should be the same size as the one for the bath not the basin i.e. 40mm 1 1/2" not 32mm 1 1/4".