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Discuss Do I need to bother with traps at all?? in the Showers and Wetrooms Advice area at Plumbers Forums
Good point, thank you. Would it be acceptable to have just a single trap just before the soak away? (i.e. a trap that would serve the sink, bath, and shower, without having individual traps at each unit) I'm not trying to cut corners, it's just that the concrete floor slab is already cast with shower drain pipe set in, would need to break up floor in order to install a trap (and then would never be able to access that trap in future without breaking up tiles and concrete). I do however have access to the main pipe just before it goes into the soak away, and could easily fit a manhole cover and accessible trap in this location.
