How to Replace a Bathroom Vanity Yourself

Replace a bathroom vanity by shutting off water, disconnecting plumbing, removing the old vanity, installing the new one, and reconnecting all plumbing connections.

1. Stop Water, Protect Floors. Shut off water supply valves under the sink by turning them clockwise. If there are no shut-off valves, turn off water at the main. Clear out all items from the vanity and lay down drop cloths to protect your flooring. Take photos of the plumbing connections before you start for reference later.
2. Detach Every Connection. Disconnect the water supply lines from the faucet using an adjustable wrench. Place a bucket underneath to catch any residual water. Remove the P-trap by loosening the slip nuts - water will spill out so have your bucket ready. If you have a garbage disposal or other connections, disconnect those as well.
3. Lift Out Sink And Top. Cut through any caulk lines around the countertop with a utility knife. For undermount sinks, remove clips from underneath. For drop-in sinks, lift straight up after cutting the caulk. Remove the countertop by lifting it off - you may need a helper for heavier stone tops. Some countertops are screwed to the vanity from underneath.
4. Pull Free The Cabinet. Remove any screws attaching the vanity to the wall - these are usually driven through the back rail into wall studs. Check inside the cabinet for screws going up into the countertop mounting strips. Once all fasteners are removed, carefully pull the vanity away from the wall. Watch for any remaining plumbing connections you might have missed.
5. Level And Mark Walls. Clean the wall surface and check for any damage that needs repair. If moving plumbing locations, now is the time to reroute supply lines and drain pipes. Check that your floor is level using a spirit level - shim the new vanity location if needed. Mark the wall studs for securing the new vanity.
6. Secure Cabinet In Place. Position the new vanity against the wall, ensuring it's level and plumb. Secure it to wall studs using 2.5-inch wood screws driven through the back mounting rail. Check that cabinet doors open properly and drawers slide smoothly. Make sure there's adequate clearance for your plumbing connections.
7. Set Top And Sink. Place the new countertop on the vanity, ensuring proper overhang and alignment. Secure according to manufacturer instructions - usually with brackets from underneath or construction adhesive. Install the sink following the specific instructions for your sink type. Apply a bead of silicone caulk around the sink edge.
8. Reconnect Water And Drains. Install the new faucet according to manufacturer directions before connecting supply lines. Reconnect hot and cold water supply lines, ensuring right connections go to right valves. Reinstall the P-trap and any other drain connections. Hand-tighten first, then snug with a wrench - don't overtighten.
9. Test, Seal, Complete. Turn water supply back on slowly and check all connections for leaks. Run water for several minutes to test drainage and look for drips. Apply caulk around the vanity base where it meets the wall and floor. Install any remaining hardware like cabinet pulls, towel bars, or mirrors.