Dear sir,I have a flat on top flora.It was nearly about 10yrs.old.The terrace of flat is covered with flooring tiles.The slop of terrace is perfect from bothsides.After heavy raining my only one room start leaking from varies spot.After stoping rain,no any water cloging on tarace.I applied waterproofing materials on tiles gaps,but could not get success.out of four rooms, this problem occurred in only one room.So pl.give me accurate suggestions?hoping fr u.thanks