How to Replace a Broken Undermount Sink in Bathroom

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Things You'll Need

  • Silicone

  • Caulking gun

  • Sink clips

  • Clean cloth

  • Screwdriver or nut driver

  • Hand drill (optional)


It may be easier to use a bar and clamps specifically made to hold the sink in place while you are installing the clips underneath the sink. If you do not have this tool, you will need another person to hold the sink while you connect the clips.

Make a small angled cut at the tip of the caulk tube, so the caulk comes out easier. Wipe up any excess caulk quickly or it will dry and be difficult to get off. Clean your hands right away if you get caulk on them or it may be hard to get it off later.


Undermount sinks are becoming a popular choice for home owners because they allow for easy cleanup and come in a variety of styles and materials. It is possible to replace a broken undermount sink yourself as long as you use the previous sink measurements as a guide for the new one. It will take a few materials to complete this task, but you will save money in the long run.

Step 1

Measure the sink to ensure it will fit in the existing sink hole. This will make the installation much easier and will cut down on excess work.

Step 2

Add a thin line of silicone caulk with a caulk gun around the upper edges of the sink bowl to ensure the sink adheres to the countertop and creates a watertight seal between the sink and countertop. Make sure the caulk is evenly applied and that you do not add too much caulk or it will squeeze out when you tighten the clips. Gently squeeze the caulk gun's handle as you run the edge against the sink's surface. Always release the trigger or caulk will continue to come out. The caulk should go on the front side of the sink's lip, around the entire perimeter.

Step 3

Climb underneath the sink hole and position the sink in place. Have another person on hand to help you hold the sink while you install the clips. The clips hook onto the lip on the underside of the sink. Space the clips evenly underneath the countertop.

Step 4

Tighten the screws with a screwdriver. You can also use a screwdriver bit and a hand drill. Wipe off any excess caulk that has seeped out with a clean cloth.

Step 5

Wait for the silicone caulk to set for 24 hours before hooking up the faucet and drain lines.


Dianne Christensen-Herman

Dianne Christensen-Hermance is an accomplished journalist with more than 10 years experience in writing news and feature articles for newspapers. She is a freelance writer for The Muskegon Chronicle in Muskegon, MI, and Demand Studios. She has a Bachelor of Science degree in journalism from Grand Valley State University.