How to Install a Wall-Mount Vanity and Sinks

A floating vanity lends clean lines and an airy feeling to nearly any bathroom, but the benefits go beyond aesthetics. In houses with out-of-level floors, hanging a cabinet and sink on the wall means you can skip right past shimming the furniture’s four feet. Also, you can customize the installed height, going above or below the standard 31 inches. Even the tallest cabinets leave a gap underneath big enough for you to tuck in a bathroom scale, slippers, or a child’s step stool. Need more room? Choose a slim, shelf-style vanity that leaves space underneath for a seat to one side of the sink, creating a morning prep area. Rigo Mocha, of Westport, Connecticut-based Classic Construction Group, installed this 72-inch-long vanity with dual sinks as the finishing touch in a spa-like modern bath, but the process is similar for cabinets of any size. You’ll need a plumber to rough in the pipes and make the final water and drain hookups. Read on and learn how to save by installing the cabinet, countertop, and fixtures yourself.

Vanity, $2,064; countertop, $1,090; backsplash, $120; sinks, $175 each; faucets, $527 each. Kohler

Step 1

Overview: How to Install a Wall-Mount Vanity and Sinks

Day-to-Day Timeline

SATURDAY Attach the bracing and hang the vanity (Steps 1-6).

SUNDAY Install the countertop and fixtures (Steps 7-15).

Step 2

Notch the Studs

Mark the vanity’s width above the rough plumbing. For a 36-inch-high countertop, make a second mark 34½ inches above the floor to represent the top of the 2×6 brace. Extend the mark with a level. Draw a second line 5½ inches lower for the bottom of the brace. Using a circular saw set to cut 1½ inches deep, make several passes to create a notch between the marks. Hammer the slivers free, then clean the notch with a chisel. Repeat to notch all the studs that will support the brace.

Step 3

Attach the Bracing

Cut a 2×6 brace 70 inches long with a circular saw. Apply construction adhesive to the notches, and press the brace into place. Fasten it at each stud with a pair of 3-inch deck screws. Have a plumber rough in the supply lines and drains for each sink, then finish the drywall, paint, and add any base molding.

Step 4

Mark the Location

Subtract the thickness of the countertop from the finished height of the vanity, ¾ inch in our case, and draw a level line at that dimension from the floor.

Step 5

Cut Plumbing Holes

Measure from the level line down to locate the water supplies and drain. Place the cabinet on a protective mat; remove the doors and set them aside. Transfer the pipe locations to the back of the vanity. Use a ¾-inch-diameter hole saw for the supply lines and a 1½-inch-diameter saw for the drainpipe. Start the hole from the outside, pushing the pilot bit through the vanity’s plywood back, then finish the cut from the inside to avoid tear-out.

Step 6

Hang the Vanity

With a helper, rest the vanity on a 5-gallon bucket topped with enough plywood scraps to raise the cabinet to the level line on the wall. Make a pilot hole with a ¼-inch-diameter drill bit through the middle of the back rail at each end of the vanity. Use an impact driver to fasten the cabinet to the wall with 5⁄16-inch lag screws and washers, checking for level as you work. With the vanity level, make more pilot holes at roughly each cabinet door bay and attach with more lag screws. Then remove the support.

Step 7

Prep for Faucets

With a helper, flip the countertop over so the underside faces up, and rest it on the cardboard-covered vanity. The countertop is indented to show a spout and four handle locations for each sink. Put on a dust mask and chuck a 1 3⁄8-inch-diameter hole saw into your drill/driver. Cut out the three holes per sink that will fit your faucet and handles, applying even pressure as you work through the countertop.

Tip: Be sure to use a hole saw for the plumbing cutouts—a paddle bit could crack the countertop.

Step 8

Apply Adhesive to the Sink

Wipe the dust from the countertop. Spread a bead of silicone caulk on the sink’s flange and tip the sink in place.

Step 9

Screw on Clips

Attach a steel clip at each corner with a screwdriver, clamping the sink to the underside of the countertop. Use a rag to wipe away any caulk that squeezes out into the bowl.

Step 10

Install the Handles

Apply plumber’s putty beneath the handles and spout. Feed the handles through the outer openings from below, taking care that when the countertop is installed HOT will be oriented on the left and COLD on the right. Make sure that in the off position the handles face away from the spout. Slip washers over the threaded ends, add the lock nuts, and tighten them with a screwdriver. Insert the spout in the center opening, then fit its two-hole washer over it. Thread on the nut and tighten with an adjustable wrench.

Step 11

Add Supply Lines

Use more putty to install the drain assembly. Thread the faucet lift rod through the spout and connect it to the drain’s stopper rod. Test the stopper. Thread the mixing tee to the end of the spout. Connect a supply line to each handle, then curl and thread them to the tee. Tighten each connection with a wrench.

Tip: Hand-tighten all the fittings; then, once everything is built, go back and cinch them a quarter turn with a wrench.

Step 12

Add the Sealant

With a helper, turn the countertop right side up and lower it onto 2×4 scraps resting diagonally across the front corners of the vanity. Add a bead of siliconized acrylic caulk to the top edge of the vanity.

Step 13

Remove the Spacers

Have a helper lower one end of the countertop after you take out the 2×4 it’s resting on. Then remove the spacer from the other end, pressing up against the bottom of the sink as you lower the countertop. Use a tape measure to check that the overhang on both ends is consistent.

Step 14

Add the Backsplash

Squeeze siliconized acrylic caulk onto the rear of the backsplash, center it over the countertop, and press it against the drywall. Add more caulk where the backsplash meets the wall and where it meets the countertop; smooth the beads with your finger.

Step 15

Replace the Doors

Push the top hinge in place first, pressing it until it snaps, then the bottom hinge. Repeat on the remaining doors. Use a screwdriver to adjust the door’s position as needed. Then have a plumber install shutoff valves under the sink and make the final connections for water and the drainpipe.