PEX Tubing, in general, better wall up against the wall. Forever. Now, success is guaranteed: a drop of a drop of water from the "street" PVC will accumulate in the ceiling between floors and one day break through to the downstairs neighbors. In the best case - in the form of swollen plaster in the bathroom. Drench all the floors (as is done in New York valiant firefighters while extinguishing the fire) you are unlikely to succeed, but the local popularity you will undoubtedly get anywhere.