How to Attach Undermount Sink

An undermount sink can add a modern and sleek element to your kitchen, while making it simple for you to clean your countertop by just wiping debris, such as food remnants, directly into the sink. Though there are several methods professionals use to install an undermount sink, one of the best way to accomplish the task is safely gluing the sink in place with a 2-part epoxy and silicone sealant, eliminating the need to drill holes into the bottom of your countertop to support studs, which could make the stone weak and then cause it to crack or break. For the best method, make use of the following steps.

1. Secure the things that you will need for the project, which include a clear or translucent silicone, 2-part epoxy, caulk gun, angle grinder, 2 24-inch bar clamps, small stone pieces, wooden brace, utility knife, acetone and rags.

2. Wipe the sink’s top lip that will contact the countertop with acetone and a clean rag. Wipe around the countertop’s bottom edge that will also contact the lip of the sink with acetone and a clean rag.

3. Insert the sink into the cabinet underneath its opening in the countertop and then apply a half-inch chord of silicone sealant around the sink’s entire perimeter, specifically on its lip that will contact the countertop.

4. Insert the bottom ends of the 2 bar clamps through the openings in the drain and then place a wooden brace that is long enough to span the opening of the sink on the countertop. Lifting the sink into place, hook the top ends of the clamps over the wooden brace for support. Tighten the clamps until the sink will be tight against the countertop’s bottom.

5. To make any adjustments to the sink, tap it on the sides with your hand. You need to position the sink in a way that the countertop overhang will be even around its perimeter.

6. With a clean rag soaked in acetone, use your finger to clean up the excess silicon that has squeezed out from the joint between the countertop and the sink.

7. Mix a small portion of 2-part epoxy on a cardboard square according to the manufacturer’s instructions and then cut eight 1×2-inch blocks of stone with an angle grinder. Apply small amounts of epoxy to the stone blocks and then position them around the sink in a way that it spans both the bottom of the countertop and of the lip of the sink. Keep in mind that a fast-setting epoxy will harden quickly, so you must work fast.

8. Finally, remove the clamps after the epoxy has hardened, but make sure that you do not hook up your garbage disposal or any plumbing fixture for about 24 hours, during which the silicone is curing.

Tips and Warnings

While you can attach an undermount sink on your own, the process will be simpler with an extra set of hands. It would also be easier when you install the supply lines and the faucet to the countertop before you set the sink. When using acetone, allow ventilation to your room and heed the warnings on the bottle.

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