"rob w" wrote in message
If you do this you will pull a vac on the basin trap and at best it
will glug when empting the bath at worst it will empty the trap
leaving you with nasty smells. If you really need to do this use a
hep'v'o air admittance valve instead of the trap on the basin. Rob


I stand corrected, but it seems to be going ok with mine. I have a shower
pipe running along and the sink waste falling down into it. That said I do
get some glugging (from the shower waste), although hardly any, when I empty
the sink. I always put this down to it being a shallow waste on the
shower...... but now I know differently I won't do the same again next
time........ no honest!