You may be hearing expansion and contraction of the copper tubing. Sometimes the holes in the wood floor or sole plate (stud) are drilled too small. In new construction we use what I call a bunny ear. It's just a plastic ring that is wrapped around the copper tubing as it passes thru the wood floor. 2 screws are then fastened to each "ear".

Have the same problem after having bathroom redone recently. Ours happens when we use the hot water and it is not the supply but the pvc drain expanding and rubbing against the studs. Bring some hot water from another part of house and pour it down your drain. If it is the pvc, which i bet it is, you'll hear the ticking. We were told not much we could do but open up the wall or live with it. The plummer blamed the drywallers for "being to rough" around his work. Whatever.

I'm sorry to hear your problem, but the simple fact in any PVC drainage situation is: IT's LOUD. Especially a stack. Tyler Pipe actually has a trademark on a no-hub cast-iron pipe called the "Quiet Pipe" You can flush 10 toilets, drain 8 tubs and 4 lavs and still not hear the water going down.There was a poster a while back saying he heard a noisy pipe. He tried to insulate to no avail. Unfortunately most residential codes allow PVC drainage, yet the plumber takes the EZ way out and fails to inform the homeowner of the PVC noise from the stack. of course no-hub cast-iron is more expensive to install, but in my opinion if I'm paying good money for a new home, no-hub would be my choice of material.

Thanks Tom, but I understand and accept the noise part of the pvc drain, that is the audible running water. My problem is with the ticking noise which I have been led to believe from sites such as this is preventable at the time of installation by putting something between the pvc and the studs. Or are you saying this is also a normal part of using a pvc drain? It seems to be it should not be and the plummer is to blame. Thanks.

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