In this video, This Old House plumbing and heating contractor Richard Trethewey installs a beautiful new bath vanity.
1. Shut the hot- and cold-water shut-off valves underneath the sink.
2. Disconnect the sink trap from the sink’s tailpiece (vertical drainpipe) by hand.
3. Use an adjustable wrench to disconnect the hot- and cold-water supply lines from the shut-off valves.
4. Slice through the old caulk around sink bowl using a utility knife.
5. Pry the old sink bowl from the vanity top.
6. Use a drill/driver to unscrew the vanity top from the vanity cabinet; remove the top.
7. Cut out the floor of the vanity using a reciprocating saw.
8. Set the new vanity cabinet into place.
9. Turn off the water at the meter or main shut-off valve.
10. Reposition the water-supply pipes, if necessary, by cutting and sweating on new copper pipes.
11. If necessary, use a handsaw to notch the cabinet back to fit around the drainpipe. Set the vanity cabinet into place.
12. Use a jigsaw to cut an opening in the side of the vanity cabinet for the existing electrical outlet box.
13. Secure electrical box to vanity with Madison bars; bend over the metal tabs on the bars to securely hold the outlet box to the vanity.
14. Screw the faceplate onto the outlet.
15. Install new shut-off valves, then finish making the plumbing connections.
16. Screw the vanity cabinet to wall.
17. Install a faucet to the sink that’s attached to the new vanity top.
18. Apply a continuous bead of silicone adhesive around top edge of vanity, then set the vanity top into place.
19. Connect the water-supply lines to the shut-off valves and to the sink faucet.
20. Use PVC primer and cement to connect the plastic drainpipe.
21. Place a bead of plumber’s putty around sink drain, then set the drain in the sink hole and tighten the nut from below.
22. Remove any excess putty that squeezes out from under the drain flange.