Fixtures PhaseStep 25 of 27

Install Bathroom Vanity

Set the vanity level, attach securely to wall studs, and connect plumbing. Proper installation prevents water damage and ensures decades of reliable use.

Quick Summary

Time

2-4 hours

Cost

$200-$1,500

Difficulty

Medium

Tools

Level, drill, wrench

Types of Vanity Installation

Installation method depends on your vanity style. Each has different mounting requirements.

Floor-Standing Vanity

Most common type. Sits on the floor with adjustable feet or toe kick. Still requires wall attachment for stability. Weight is supported by floor, making installation easier.

Easiest installation • Best for uneven floors • Most forgiving

Floating (Wall-Mounted) Vanity

Mounts directly to wall with no floor contact. Creates modern look and easier floor cleaning. Requires heavy-duty mounting brackets and must hit wall studs. No room for error.

Modern look • Harder installation • Must hit studs

Semi-Recessed Vanity

Basin partially extends forward over countertop. Common in small bathrooms to save space. Requires precise countertop cutout and careful sink positioning.

Space-saving • Specialized installation • Precise measurements needed

Installation Steps

1

Position and Check Level

Place the vanity in position. Use a 4-foot level to check front-to-back and side-to-side. Most floors are not perfectly level. Check both the top rim and the sides for plumb. Mark the floor position with painter's tape.

Pro tip: Check level in multiple spots across the vanity top. A long level is essential - short levels can be misleading on uneven surfaces.
2

Shim to Level

Use plastic or composite shims under the low corners or along the base. Insert shims, check level, adjust as needed. Once level is perfect, mark shim positions with pencil, pull vanity out, and trim shims flush with a utility knife.

Important: Don't skip shimming. An unlevel vanity causes countertop stress, door misalignment, and water pooling on countertops.
3

Locate Wall Studs

Use a stud finder to locate studs behind where the vanity will sit. Mark stud centerlines on the wall at the height of the vanity mounting rail (usually 2-3 inches from top). You need to hit at least two studs, preferably three.

For floating vanities: If studs don't align with mounting points, you'll need to install blocking between studs during framing. Plan ahead.
4

Drill Pilot Holes

Position the vanity on its shims. From inside the cabinet, drill pilot holes through the mounting rail into the studs. Use a drill bit slightly smaller than your screw shaft. This prevents splitting the stud and makes driving screws easier.

Tip: Mark your drill bit with tape at the correct depth to avoid drilling through the front of the stud into the room.
5

Attach to Wall Studs

Drive 2.5-3 inch wood screws through the pilot holes into studs. Don't over-tighten - you'll crack the vanity back. Tighten until snug, then stop. For floating vanities, use the manufacturer's mounting brackets and follow weight rating specifications exactly.

Screw placement: Place screws 2-3 inches below the top edge at each stud location. Add additional screws every 16 inches along mounting rails.
6

Install Countertop and Sink

If countertop is separate from vanity, set it in place and secure per manufacturer instructions (usually silicone adhesive). Install faucet and drain assembly before setting countertop if access will be tight. Drop-in sinks install after countertop; undermount sinks attach before.

One-piece tops: Many vanities come with integrated top and sink. These simply rest on the vanity box with silicone at the back edge.
7

Connect Plumbing

Connect hot and cold supply lines to shutoff valves. Hand-tighten, then snug with wrench 1/4 turn. Install P-trap connecting sink drain to wall drain pipe. Don't use plumber's tape on compression fittings - they have rubber washers.

Testing: Turn on water slowly, check all connections for leaks. Run water for 5 minutes. Check supply lines and P-trap joints. Tighten if needed.
8

Caulk and Final Details

Apply a bead of silicone caulk along the back edge where vanity meets the wall. Also caulk around the countertop edge if it's separate from the vanity. Tool with wet finger for smooth finish. Install cabinet hardware (knobs, pulls) last.

Caulk color: Use clear silicone or color-matched caulk. Let cure 24 hours before using the sink heavily.

Common Mistakes to Avoid

Not Leveling Properly

An unlevel vanity causes doors to swing open or closed on their own, drawers to stick, water to pool on countertops, and stress cracks in stone or quartz tops. Always use a 4-foot level and shim until perfect. Don't rely on the floor being level.

Missing Wall Studs

Drywall anchors are not strong enough to hold a vanity, especially floating vanities. Always attach to studs with proper wood screws. If studs don't align, install horizontal blocking during framing, or use a different vanity size that hits available studs.

Over-Tightening Plumbing Connections

Plastic P-trap fittings and supply line nuts can crack if over-tightened. Hand-tight plus 1/4 turn with a wrench is sufficient for compression fittings with rubber washers. If it leaks, replace the washer rather than cranking it tighter.

Installing Faucet After Countertop

If space is tight, installing the faucet after the countertop is in place makes tightening mounting nuts very difficult. Always test-fit first. If access is limited, install the faucet and drain assembly on the countertop before setting it on the vanity.

Forgetting Shutoff Valve Access

Position the vanity so you can still reach shutoff valves and P-trap connections. Some vanities have removable back panels or access cutouts. Don't permanently block access - you'll need to reach these for future repairs.

Frequently Asked Questions

Do I need to attach a vanity to the wall?

Yes, always attach vanities to wall studs for stability and safety. Even floor-standing vanities should be screwed to the wall to prevent tipping. Floating vanities absolutely require secure wall mounting with heavy-duty brackets, as they have no floor support. Use minimum 2.5-inch screws into studs, hitting at least two studs.

How do I level a vanity on an uneven floor?

Use plastic or wood shims under the vanity base to level it. Place shims at low points and check with a 4-foot level across the front and sides. Once level, mark shim positions, remove vanity, trim shims flush with a utility knife, and reinstall. Most floors are slightly uneven, so shimming is normal and necessary for proper countertop seating.

Can I install a floating vanity without hitting studs?

No, floating vanities must be anchored into wall studs. They support the entire weight of the vanity, countertop, sink, and water with no floor support. Toggle bolts or drywall anchors are not strong enough for floating vanities. If studs don't align with your vanity mounting points, install a horizontal 2x6 or 2x8 backing board between studs during framing.

Should I install the faucet before or after setting the countertop?

Install the faucet before setting the countertop if access will be tight. It's much easier to tighten mounting nuts and connect supply lines when working on a flat surface. If you have good access from below (open vanity or removable shelf), you can install the faucet after. Test-fit first to determine which approach works better.

How tight should I make plumbing connections?

Hand-tighten all connections first, then use a wrench to snug an additional quarter turn (90 degrees). Over-tightening can crack fittings or strip threads. For supply lines with rubber washers, hand-tight plus 1/4 turn is usually sufficient. For P-trap connections, hand-tight is often enough since they have large rubber gaskets.