Stop Struggling! Here's How to Easily Remove an Undermount Sink

An undermount sink can be a beautiful addition to any kitchen remodel. However, when it comes time to replace an old undermount sink, many homeowners struggle with the removal process. Trying to wiggle the sink loose from its snug mounting without damaging the surrounding countertop can be tricky. Cutting through layers of silicone sealant while supporting the heavy sink's weight is no easy task either.

But removing an undermount sink doesn't have to be a headache. With some basic tools, patience, and the right techniques, you can remove your old undermount sink quickly and safely. Follow this simple step-by-step guide to learn how.

Step 1: Disconnect the Plumbing

Before attempting to remove the sink itself, the first step is disconnecting all the plumbing connections. This involves shutting off the hot and cold water supply valves below the sink. Use a basin wrench to loosen the supply line nuts where the supply tubes connect to the faucet and shut-off valves. Remove the tubes.

Next, unscrew the P-trap connecting the sink drain pipe to the wall stub-out. Set a bucket underneath to catch any water still in the pipes. Also unscrew the dishwasher discharge tube if you have one hooked up.

Lastly, if you have a garbage disposal, disconnect its drain tube from the sink drain as well as its power supply. With all the plumbing detached, you're ready to move on to removing the actual sink.

Helpful Plumbing Removal Tips:

• Label supply tubes for hot and cold to make reconnecting easier
• Protect faucet finish by covering with towel before disconnecting
• Snip P-trap with mini hacksaw if unable to unscrew by hand

Step 2: Remove Mounting Hardware

Undermount sinks are secured in place with mounting clips, brackets, or rails that attach to the bottom of the countertop. Locate these around the perimeter of the sink. Using a drill or screwdriver, carefully detach the clips from the countertop.

Take care when removing any mounting hardware as it is often the only thing holding up the sink at this point. Have a helper on hand to support the weight of the sink from above as you remove the clips. Once all clips are detached, the sink should be ready to lower out.

Mounting Hardware Removal Tips:

• Protect countertop with towel when removing clips
• Start with clips at back of sink for support as you work
• Use pry bar for extra leverage removing stubborn clips

Step 3: Break Sealant Seal

With the sink no longer secured, the next challenge is breaking the watertight seal around its perimeter. This is usually a pliable silicone caulk or sealant. Start by running a utility knife carefully along the seam between the sink and countertop.

Next, take a stiff putty knife and begin working it into the silicone sealant seam. Apply force in small increments, piercing through the bead of caulk. Use a gentle back-and-forth wiggling motion. Work slowly around the entire sink edge, breaking the sealant's grip little by little.

Patience and care are crucial here to avoid damaging the countertop material or chipping the sink. Take frequent breaks and reinsert putty knife at new spots periodically. The sealant will eventually separate from the countertop.

Silicone Sealant Removal Tips:

• Try dental picks for precise caulk separation in tight spots
• Heat sealant with hair dryer to soften before prying
• Place shims to stabilize sink if it starts shifting

Step 4: Clean Away Adhesive

Once you've cut through the silicone seal and freed the sink, inspect the underside of the countertop. There is often some stubborn adhesive residue left behind after removing old caulk. This needs to be scraped off to provide a clean surface for the new sink.

Use a plastic putty knife, being careful not to gouge or scratch the countertop material. Rubbing alcohol on a cloth can also help break down and remove leftover adhesive buildup. Be thorough in cleaning the entire perimeter until only the bare countertop remains.

Also take this opportunity to remove any wooden support brackets or braces that were securing the original undermount sink. Unscrew them using a drill or screwdriver. Patch holes with putty if desired.

Countertop Cleaning Tips:

• Try denatured alcohol for really stubborn adhesive spots
• Hold razor blade at 30deg angle when scraping caulk
• Use painter's tape for protection around scraped areas

Step 5: Lift Out Old Sink

Here comes the tricky part - safely maneuvering the sink up and out without damaging the surrounding counter. Have a strong helper on hand if needed. Get a secure grip on the sink rim before attempting to lift.

Carefully tilt and rotate the sink as you hoist upwards. Take your time and adjust angles slowly to get it through the counter hole cleanly. Keep your fingers well clear of pinch points where the sink could shift or slip.

For heavy cast iron sinks, resting plywood across the countertop opening can support the weight as you lift. Just don't let the edge of the sink hit the counter as it comes out. Patience and coordination are key throughout this step.

Safe Sink Lifting Tips:

• Use suction cups to get a grip on slick sinks
• Twist sink slightly to break any remaining sealant spots
• Get help for double sinks which are very heavy

Step 6: Prep for New Sink Installation

With the dirty work done, do a final inspection of the countertop sink area. Ensure all adhesive, debris, caulk, and mounting hardware has been completely removed. Verify the counter hole dimensions match your new sink.

Make any edge repairs to the countertop opening using epoxy if the removal process caused cracks or chips. Sand down rough areas around sink cutout. Then clean the entire surface well using denatured alcohol.

Once prepped, you can start installing your shiny new undermount sink following the manufacturer's instructions. Admire your work and relish in conquering one of the toughest sink replacement jobs.

Troubleshooting Tricky Removal Challenges

Even carefully following these steps, undermount sink removal sometimes hits snags. Here are some common challenges and fixes:

Silicone Sealant Won't Cut

For rock-solid silicone that won't budge, soften it first with a heat gun or chemical solvent like acetone. Peel away slowly and patiently. If needed, break away chunks with a chisel rather than pry up.

Sink Shifts or Drops During Removal

Have helpers support sink weight from below. Place shims or pry bars around the sink edges to stabilize it. Take it slowly and adjust your grip as needed.

Adhesive Coating Won't Scrape Off

Adhesive cleaner, a razor blade scraper, and elbow grease should remove the most stubborn caulk remnants. Try a gentle chemical solvent like acetone only as a last resort.

Countertop Gets Gouged or Chipped

Minor surface damage can often be smoothed over with sandpaper and solid surface epoxy filler. For more significant damage, consult a countertop installation pro.

As you can see, removing an undermount sink takes time, patience, and the proper techniques. But now that you understand the process, you can tackle this project with confidence. Just be sure to enlist an extra pair of hands when needed.

Following each step carefully from shutting off plumbing to wiping away the last bit of old caulk, you'll free the sink without issue. Then you can complete your kitchen renovation by installing an eye-catching new sink.