How to Install an Undermount Stainless Steel Sink to a Quartz Countertop

Installing an undermount stainless steel sink to a quartz countertop can seem daunting, but with the right tools and techniques, it can be a straightforward DIY project. Here is a step-by-step guide on how to install an undermount sink to a quartz countertop.

Planning and Preparation

Before starting the installation, make sure you have all the necessary supplies:

  • Undermount stainless steel sink
  • Quartz countertop
  • Silicone caulk (neutral cure recommended)
  • Caulk gun
  • Screws suitable for securing the sink clips
  • Rags
  • Denatured alcohol
  • Safety glasses and gloves

Ensure the quartz countertop is properly supported, level, and has had any cutouts made prior to installation. Have the sink on hand to test fit before attaching.

Step-by-Step Installation

Follow these steps for proper undermount sink installation:

Clean the Countertop

Thoroughly clean the underside of the countertop where the sink will be installed using denatured alcohol. This removes any dirt, grease or debris that could interfere with the caulk adhering.

Wipe the top side of the countertop as well, particularly around the sink cutout.

Apply Silicone Caulk

Run a generous bead of silicone caulk around the top edge of the sink. Use a smooth, continuous line and make sure there are no gaps.

The caulk provides the water-tight seal between the sink and countertop. Using neutral cure silicone specifically formulated for kitchen and bath provides the best adherence and flexibility.

Position the Sink

Carefully set the sink into the cutout hole in the quartz countertop. Press firmly from above to adhere the sink into place in the caulk.

Make sure the sink is centered and aligned properly before securing.

Install Sink Clips

Most undermount sinks include metal clips to help hold the sink in place while the caulk sets. Position a clip near each corner and space additional clips every 6-8 inches along the sink edge.

Tighten the screws just until they are snug – overtightening can cause the quartz to crack.

Allow Caulk to Cure

After installing the clips wipe away any excess caulk with a damp rag. Remove any caulk on the countertop top side as well.

Allow the caulk to cure fully (typically 24-48 hours) before using the sink. Running water or putting weight on the sink before the caulk has set can compromise the seal.

Apply Sealant Bead

Once cured, apply a secondary bead of caulk along the seam between the sink edge and countertop. This provides added protection from moisture getting under the sink rim.

And that’s it! With the right planning and preparations, installing an undermount sink into quartz is a straightforward project. Just take your time and ensure proper adhesion and seal.

FAQs About Installing an Undermount Sink in Quartz

Here are answers to some frequently asked questions about installing undermount sinks in quartz countertops:

What kind of caulk is best for attaching an undermount sink?

Use a premium neutral cure silicone caulk designed for kitchen and bath applications. Avoid acrylic latex caulks. Ensure the caulk adheres well to both stainless steel and quartz.

How long does the caulk need to cure before using the sink?

It’s best to allow the caulk to fully cure for 24-48 hours before running water or putting any weight in the sink. This ensures a tight, waterproof seal.

What is the purpose of the sink clips?

The clips take the weight of the sink instead of the caulk having to bear all the weight. They also hold the sink in place while the caulk fully sets.

Should I caulk the seam between the sink and countertop after install?

Yes, applying a secondary sealant bead after the main caulk has cured provides added leak protection. It fills any small gaps left after clipping the sink in place.

What is the best way to cut the hole for an undermount sink?

For quartz, it’s best to have your countertop fabricator or installer cut the sink hole using specialized tools. This prevents cracking or chipping the quartz.

How can I remove an existing undermount sink from a quartz countertop?

Carefully cut away the caulk bead with a utility knife. Remove the clips and screws. Apply firm but careful pressure to break the sink free from the caulk seal. Go slowly to avoid damaging the quartz.


Installing an undermount sink provides a seamless, stylish look for a quartz countertop. With some basic skills and the right materials, it can be successfully accomplished as a DIY project. Preparation is key – ensure the countertop is ready, take time fitting the sink, and allow the caulk to fully cure before use. Follow the steps outlined here closely, and you can have a beautiful and functional undermount sink that will provide years of service.