How to Attach an Undermount Sink on a Stone Countertop
- 1). Line up the sink with the cutout inside the countertop. Position the sink so the sides are flush with the cutout. Remove the sink and attach the undermount hardware to the side of the sink. Tighten the screws with a screwdriver.
- 2). Brush the epoxy or adhesive supplied by your sink manufacturer on the undermount hardware.
- 3). Run silicone around the top of the sink on the horizontal lip that forms the sink edge with a caulking gun. This part of the sink is called the flange, and it is the part of the sink that sits flush to the underneath side of the stone countertop.
- 4). Line the sink up with the cutout again and press it to the underside of the countertop. Let the epoxy or adhesive set for 15 to 20 minutes.
- 5). Install the clips and wing nuts to the undermount hardware and tighten the wing nuts, if your faucet hardware includes clips. If not, skip this step.
- 6). Apply a bead of silicone around the edge of the sink to seal the seam between the sink's flange and the bottom of the countertop.
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