Bathroom Basin Replacement

Some of you may remember visiting model homes years ago. The simulated or “cultured” marble or onyx vanity tops in the bathrooms were stunning. The one-piece construction basin and top was an attractive and relatively maintenance-free feature.

Cultured solid surface countertops continue to be popular; today’s tops being far superior to those manufactured in the ’70s and early ’80s. As a result, there are a lot of non-vintage cultured marble and onyx basins around that are unsightly, to say the least.

What should you do to remedy that circumstance? One alternative is to remove the entire countertop basin and all and replace it with a new one. However, in order to get the top out, you would need to remove the surrounding splashes which could damage the paint or wallpaper. Or even remove a mirror or medicine cabinet.

Alas, you don’t need to remove the countertop to resolve the basin problem. Simply remove the existing basin and replace it with a new one.

Before removal, shop for a replacement basin. Vitreous china, enameled cast iron and acrylic are three popular choices that are attractive and durable.

The replacement basin should be of the self-rimming variety the rim at the perimeter of the basin sets atop the countertop. This style is necessary to conceal the raw opening created when the old bowl is removed. Size is important too. Look for a basin that will fit within the space allowed. Most modern bathroom vanity countertops measure about 21″ from front to back, and will accommodate a 19″ basin measured from the outside edge of the front rim to the outside edge of the back rim.

Additionally, many cultured countertops are manufactured with holes for the faucet. The new basin should have such holes. Be sure to get a basin with the correct hole configuration either four-inch or eight-inch. Since you need to remove the faucet in order to get the old basin out, you might want to consider installing a new one.

Start the basin replacement process by removing all personal items on the top. Remove the contents of the vanity since you’ll be creating a lot of dust. Protect the floor and other surrounding finishes that might be damaged.

Remove the faucet and drain assembly. Turn off the hot and cold valves located under the sink, and disconnect the water supply lines. Use a basin wrench to remove the nuts that anchor the faucet at the underside of the countertop. Before removing the drain assembly, place a bucket just below it to catch water that remains in the trap. A pair of channel locks works well in disassembling the drain and P-trap.

With the faucet and drain assembly out of the way, mark your cut line for the opening required to accommodate the new basin. Use the template packaged with the basin along with a medium-point black felt tip marker to trace the cut line onto the countertop. Drill a pilot hole along the inside edge of the line. Next, insert the blade of a reciprocating saw into the pilot hole and carefully cut along the line. Choose a medium to fine blade for an accurate and cleaner cut. Apply a layer of duct tape to the face of the saw table to avoid scratching the countertop. For safety, wear eye protection and a dust mask.

Once the cut is complete, remove the old basin and lightly sand or file the rough edge. Use a vacuum to clean up all of the dust and mess created by the cutting process. It’s important that the surface be clean and dry when installing the new basin.

A trick that will save some time and aggravation when replacing the faucet: Attach the faucet to the basin BEFORE installing the basin. Thus, the faucet can be assembled from above rather than making you work on your back with a basin wrench. It also helps to attach the water supply lines to the hot and cold connections at the faucet, and install the drain before the basin.

You’re ready to set the new basin. Apply a thick bead of silicone caulk to the underside of the basin rim. Carefully place the basin into the opening and onto the countertop. Gently work the basin back and forth to cause it to seat properly, assuring a secure connection. Check that the basin is centered, properly aligned and flush to the countertop.

After the new basin has been allowed to sit for several hours, reconnect the drain assembly and attach the hot and cold water supply lines to the valves. Open both valves completely.

Finish the job by applying a thin bead of silicone caulk along the joint where the basin meets the countertop. This will provide an easy-to-clean and waterproof connection.

Plan to spend about half a day, and between $75 and $200 for a good quality basin. Caulking and incidentals should be less than $10.

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