combined bath and shower waste run All aspects of plumbing questions and answers, help, tips and information

[mscg]

is there a specific type of trap that will prevent bathwater finding its way back along the shower waste or is the seal created by the water in the shower trap sufficient. the trap that was there was a low level bath trap with anti-vac - could i replace with a basic bottle trap or with the pressure created by the head of bath water push the trap out

[thedoctor]

There is no "specific" trap as its expected that both units will have enough fall to prevent this possiblity. A bottle trap is not recommended for a bath but you can put a normal s bend on.

[smithy]

If you have only a slight fall on your waste pipes.
you could insert a inch and a half Mcalpine non return waste valve, to combat waste water from bath being forced up into shower tray.
they are available from plumbers merchants or even B and Q and Wickes.

Hope This Helps,
Smithy