How To Install a New Vanity Sink Top
Small changes make a big difference when you want to update the look of your bathroom. Installing a new vanity sink top is one of those changes that require minor effort, but result in a huge difference in appearance and functionality. Usually the sink vanity cabinet is is good shape, but the current vanity top is dull or has a lot of damage. Installing a new vanity top requires some measuring and planning, but is doable project for any homeowner.
Tools and Materials
100-grit sanding belt
Measure The Existing Vanity Top
Measure the length and width of the existing vanity top with a tape measure. Since you are keeping the existing vanity cabinet, you want a top that fits the cabinet and doesn't overhang too much. Take the measurements with you when purchasing the new vanity top to ensure you get the proper size for your cabinet.
Consider adding a new faucet to compliment the new vanity top. When purchasing a new faucet, be sure to choose one that fits the faucet holes of the new vanity top. The faucet completes the look of your new vanity top.
Remove The Existing Vanity Top
Turn off the water supply valves under the sink. Turn the valve handles clockwise to shut off the water. Turn the faucet on to relieve pressure in the lines and drain out any remaining water.
Place a bucket under the sink P-trap. The P-trap is the portion of the drain line that makes a hook. Disconnect the faucet water supply lines from the supply valves with a wrench, and place the ends of the lines in the bucket.
Loosen the nut securing the P-trap to the sink drain tailpipe with a pair of slip-joint pliers. The tailpipe is the straight portion of pipe coming down from the sink drain. In many bathroom sinks, the tailpiece also has a linkage connecting to it from the faucet. The linkage controls the pop-up stopper. If you are installing a new faucet, it is not necessary to disassemble the linkage. Loosen the nut securing the P-trap to the line going to the wall. Once you remove the vanity top, swing the P-trap to the left or right to give you room when installing the new vanity top.
Look under the vanity top for any screws or clips securing it to the sink vanity frame. Remove screws and clips with a Phillips screwdriver. Score along the seam between the vanity top and the wall with a utility knife, especially on the rear backsplash. The backsplash is the part of the vanity that extends up the wall a few inches. Scoring cuts the paint and caulk between the wall and the vanity top.
Insert a small pry bar between the cabinet frame and the bottom of the vanity top on an outside corner. Begin prying the vanity top away from the cabinet frame. Move the pry bar to different areas between the vanity top and cabinet, prying as you go. Once the vanity top is loose from the cabinet, lift it off the cabinet and set it out of your way. Depending upon the size of the vanity top, it might be a good idea to have a friend help you lift it off the cabinet.
Scrape any remaining caulk or glue off the top of the cabinet frame with a sharp, rigid putty knife. The top of the frame must be as clean as possible.
Install New Vanity Sink Top
Place a 4-foot level across the top of the frame, with the ends of the level pointing to the sides of the cabinet. Although the cabinet was probably level when first installed, it might be out of level due to the house settling over time. If the cabinet is out of level, look for the screws securing it to the wall. Remove the screws and place shims under the cabinet as necessary until it is level.
Move the level so that the ends of the level are pointing to the front and back of the cabinet. Again, shim under the cabinet until it is level. Reinstall the screws to secure the cabinet to the walls.
Place the new vanity top on top of the cabinet. Check to ensure the back and side of the vanity fit the wall squarely. If it doesn't, it is necessary to scribe the vanity. Place a pencil in a compass. You remember what a compass is, we used them in elementary school. Place the point end of the compass on the wall, with the pencil resting on the edge of the vanity top. Slide down the wall the length of the vanity, drawing a light line on the vanity top.
Put the vanity top on a pair of saw horses and have your helper hold it steady. Sand the edge of the vanity with a belt sander and 100-grit sanding belt up to the scribe line. Retest the fit of the vanity.
Install the new faucet into the vanity top according to the directions from the faucet manufacturer. Install the faucet supply lines onto the faucet per the directions from the faucet manufacturer. This is also the time to install the new sink drain into the sink that comes with the faucet.
Apply a bead of construction adhesive to the top of the vanity cabinet with a caulk gun. Place a bead on the top of all cross members of the vanity as well as the outside edges.
Set the vanity top on the top of the cabinet, pressing it down to ensure good adhesion. Reconnect the P-trap to the sink drain tailpipe and tighten both P-trap connecting nuts.
Run a bead of silicone caulk between the seams where the vanity top meets the wall with the caulk gun. Enjoy your new bathroom sink vanity top.