How To Install Undermount Bathroom Sink

How to Install an Undermount Bathroom Sink

Nestled beneath the countertop, undermount sinks offer a sleek and modern aesthetic to any bathroom. Installing one requires precision and attention to detail, but with the right tools and guidance, you can achieve professional-looking results.

Preparation

Gather the necessary materials: undermount sink, countertop with sink opening, silicone sealant, drill, drill bits, jigsaw, and clamps. Ensure the sink fits snugly within the countertop opening.

Create Sink Support

Cut braces or supports from 1x4 lumber or plywood to fit around the sink's rim. These supports will provide additional stability once the sink is installed.

Secure Braces

Position the braces inside the countertop opening and secure them with screws or adhesive. These supports will hold the sink in place and prevent it from sagging.

Apply Sealant

Apply a generous bead of silicone sealant around the outer edge of the countertop opening. The sealant will create a watertight seal between the sink and countertop.

Insert Sink

Carefully insert the sink into the opening, aligning it with the sealant bead. Press down firmly around the edges to ensure proper adhesion.

Clamp and Support

Use clamps to secure the sink in place while the sealant dries. Place supports beneath the sink to prevent it from moving or falling.

Wait for Sealant to Cure

Refer to the sealant manufacturer's instructions for curing time. Typically, it takes several hours or overnight for the sealant to fully cure and become watertight.

Drill Faucet Holes

Once the sealant is cured, mark and drill the holes for the faucet and any other fixtures. Use a drill bit appropriate for the size of the fixture mounting bolts.

Install Faucet and Fixtures

Mount the faucet and any other fixtures, following the manufacturer's instructions. Ensure all connections are secure and watertight.

Caulk around Edges

Apply a bead of clear caulk around the edges where the sink meets the countertop. Smoothen the caulk with a damp finger or tool to create a finished appearance.