i am currently in the process of relaying some old edwardian quarry tiles on a porch floor that is partially open to the elements .i am thinking of putting in some kind of water drainage combined with a suitable fall in the floor level to help get rid of the rain water .there is a water drain pipe running through the floor already to an outside drain so i was thinking of tapping into that somehow. is there products out there that can be combined with tiles which will do the job .any ideas please