Step 1: Identify the Sound

Determine the area where the sound is coming from. Next, use a drywall saw to cut a hole in the wall and expose the area. Use a mirror to get a better look at the problem causing pipes and assess the situation.

Step 2: Install the Insulation

To prevent friction between pipes in close quarters, install insulation around the pipes, using roofing felt as a buffer under the PVC pipe.

With the felt in place, squirt polyurethane expanding foam into the gap between the pipe and the subfloor. This will isolate the noisy pipe.

Step 3: Patch the Drywall

Close up the hole with a new piece of drywall, and screw it in place. Apply drywall mud and tape to seal the hole. Allow this first coat to dry. Sand down the area and apply a second coat of drywall mud. Once the second layer is dry, sand down and paint to finish.