Step 7 · Test for Leaks

This is the step people usually slow down on. Go finger-tight first, then a quarter turn. No rush — replay the clip whenever it helps.

Ensure your bucket is still positioned under the P-trap. Place the stoppers in both sink drains and fill both bowls about halfway with water. While the sinks are filling, visually inspect all your new connections. Once filled, remove both stoppers simultaneously to send a large volume of water through the new drain system, which puts the joints under pressure. As the water drains, meticulously check every connection point for any signs of moisture. Run a dry paper towel under each slip nut and joint, as this will make even the smallest drip immediately visible. If you find a leak, the most common cause is a misaligned slip washer or a nut that isn't tight enough. Try tightening the leaking nut slightly. If the leak persists, disassemble that specific joint, ensure the washer is seated flat and correctly, and then reassemble and re-tighten.