things you will need
- Seal silicone
- Two by four board, longer than the sink opening
- Large C clamp
- Mounting clips for sinks
Undermount kitchen sinks not only look more aesthetic in modern kitchens, they also make cleaning easier as there is no rim for food crumbs and scraps to get caught. Since the sink does not hang by the rim over the fixed worktop, it must be fully fixed and sealed at the bottom to prevent leaks.
Wipe the underside of the countertop where the sink will be attached with a duster.
Squeeze a thin line of silicone around the edge of the sink. Most undermount sinks have a 1 inch rim that sits flush with the underside of the countertop. Apply the sealing ring to this rim. The sealing ring expands when the sink is pressed against the stone, creating a watertight seal.
Lay a 2-by-4 board across the countertop and across the sink opening. Align the sink under the sink opening and press against the stone. Insert one end of the clip through the sink drain and hook the other end over the panel. Tighten the clamp. This will hold the sink in place while the glue dries.
Mix the two-part epoxy. Apply a small amount to the ends of the sink mounting brackets. Press the stems against the countertop next to the sink at regular intervals around the perimeter of the sink. Allow the epoxy to dry for 10 minutes.
Apply more epoxy to the clip area of the mounting clips. Press the clips onto the sink to allow the end of the clip to slide over the mounting post attached to the countertop. Allow the epoxy to dry for 10 minutes.
Slide the ends of the clips over the stems. Tighten the screws on the clips to hold the sink securely in place with a wrench. Allow the epoxy to fully cure for at least 24 hours. Remove the clamp and attach the drain.
Tip: Stone dust often accumulates on the underside of the countertop around the sink opening while the opening is being cut. This dust can affect the sink's connection to the countertop if not removed.