When I moved into my flat there was no shelf under the sink due to the plumbing for the sink, washing machine and 0.5 bowl sink. My brother who works with a plumbing firm suggested a "flat trap" which enabled me to put in a shelf because the plumbing was not as low down. My question is, where the connection for the washing machine waste connects under the sink and into the flat trap is it enough of a drop for the waste coming out of the machine to drain away quick enough or could this connection be too slow for the waste to drain away and maybe go back down into the machine and possible damage the pump? The water sometimes comes up into the sink for a few minutes then drains quickly away and I never have a problem with the water draining away from either sink when doing dishes etc.



Thanks

Stuart