Installing sink drain assembly. Helpful Tips Be prepared to replace the shutoff valves, as they can break easily. Watermove Water Management September 7, September 7, Any excess adhesive is then wiped away with a wet cloth from underneath the countertop. This means that they are not removed but end up in rivers and lakes or even in ground water. Fill the sink, check for leaks around the drain, then drain the water and check the waste line joints. During this process you also have to decide on a faucet for your vessel sink. A 12" diameter hole would leave you a lip about 3" tall assuming an original sink height of 5. Once adult search tav faucet is mounted, the same process of connecting the supply lines to the threaded connector on the water supply pipes would apply. Examine the pipes under the sink.