Caulk is a sealing material that can waterproof the edges of your kitchen sink for years. But over time, even the strongest sealant can crack and wear away. When this happens, you need to clean and recaulk your kitchen sink to keep the edges watertight.
Even if you’ve never caulked before, it’s easy to learn, and it’s an important maintenance skill to have to keep your sink working effectively. This guide will walk you through how to caulk the kitchen sink once the old sealant has started to fail.
How To Recaulk Kitchen Sink
If your kitchen sink is leaking around the edges, it’s time to recaulk. Luckily, this is a fairly simple process that you can do on your own with just a few items and a little extra time.
What You’ll Need:
- Warm water
- Towel or washcloth
- Denatured alcohol
- Straight razor blade
- Painter’s tape
- Painters’ tool
- Paper and/or towels
- Old towels or drop cloths
- Gloves (optional)
1. Soften The Old Caulk
Caulk can either be water-based or silicone-based. You need to soften caulk before removal, and each type of caulk requires a different method for softening.
For water-based caulk (also known as latex caulk), soak a towel or washcloth in warm water and apply it to the caulk around your sink.
For silicone-based caulk, soak the towel or washcloth in acetone or denatured alcohol instead of water.
Each method will require two to three hours of soaking before the sealant is soft enough to remove.
2. Remove The Old Caulk
Place old towels or drop cloths on your kitchen floor for easy cleanup. Once the caulk has been softened, use a straight razor blade to carefully cut the old caulk away from the edges of the kitchen sink.
Be careful when using the razor blade; use thick rubber or cut-resistant gloves to protect yourself and be careful not to scratch too hard against stainless steel or metal sinks.
Remove as much of the old caulk as possible so the new caulk can adhere to your sink better.
3. Pre-Clean The Sink And Apply Tape
Wipe away any remaining debris from the old caulk with a cleaning cloth and acetone or denatured alcohol. Make sure the entire edge of the sink and counter are dry before continuing.
To keep the edges of your caulk neat and discreet, apply painter’s tape around the edges of your countertop and your sink. This will prevent the caulk from spreading too far in either direction. You want your caulk seal to be as unobtrusive as possible.
4. Apply The New Caulk
A caulking gun is the most convenient way to apply new caulk to a sink. Follow the manufacturer’s instructions to load the gun with a caulk tube.
If you choose not to use a caulk gun, snip the applicator end of your caulk tube at a 45-degree angle. Insert either a long, thin nail or a piece of sturdy wire into the hole to puncture the inner seal. Squeeze the tube as you move the tip along your sink to apply the caulk.
Apply a thin strip of caulk to the edge of your kitchen sink at a 45-degree angle. Be sure to apply enough pressure to fill the joint between the sink and the counter with caulk.
Carefully spread the caulk so it covers the edges of both the sink and countertop. You can use a caulking or painter’s tool, or even just a gloved finger.
If using the finger method, wet the finger of the glove with denatured alcohol (for silicone caulk) or water (for latex caulk).
If there are any gaps, apply a small amount of caulk and smooth it over with the rest.
Slowly remove the painter’s tape from your counters and sink. Peel the tape at an angle away from the seal, not parallel.
5. Allow The New Caulk To Dry
Do not use your kitchen sink for at least 24 hours after applying the new caulk. This gives the sealant time to dry completely and maximize the waterproofing of your sink edges.
For best results, follow the cure time listed on the manufacturer’s label of the caulk.
Which Caulk To Use
There are several different types of caulk, but for stainless steel or metal sinks, silicone-based caulk is the best choice. Pure silicone caulk is a premium material that provides a great watertight seal for high-moisture areas like your kitchen sink. If you have a porcelain sink, you can use a latex caulk instead.
You should also choose a color of caulk that best blends with your sink and countertops. If you’re using silicone caulk for your kitchen sink, you can often find it in a clear finish.
You can also choose colors like black, white, or gray. For the cleanest look, pick a color that doesn’t stand out too much against the rest of your décor and fixtures.
How do you recaulk an undermount kitchen sink?
An undermount sink is supported from below and placed underneath a section of the countertop that’s been cut out. You must remove the sink completely from the countertop before recaulking.
Be sure to shut off the water and remove all of the plumbing from underneath the sink.
Since the counter is not offering any support to the sink, it is much easier for the two to separate over time. This is why you should use a strong silicone caulk when recaulking an undermount sink.
Use the above methods to remove the old sealant from your sink, then apply the new caulk directly to the rim of the sink. Then replace the sink into its space on the counter and clamp it in place before the caulk dries.
Wipe away any excess caulk that might have seeped through the edges of the sink before it dries.
Always wait at least 24 hours before using your sink again after recaulking.
What is the best sealant for a drop-in sink?
A drop-in sink sits in a pre-cut section of your countertop with the sink edges sitting on top of the counter. Because the counter is supporting the sink, it’s not necessary to use silicone caulk.
However, silicone caulk offers stronger water resistance than latex, and it is still the best sealant for your drop-in kitchen sink.
How often should you recaulk a kitchen sink?
It isn’t necessary to recaulk too often. Caulk typically lasts between 3 and 5 years, especially with proper care.
To ensure your sink remains watertight, watch out for signs that your sink is ready to be recaulked.
You can extend the life of your caulk with proper maintenance. Clean up any spills as they happen, and every few months apply a mild vinegar and water solution. Let it sit for a few minutes, then scrub the caulk with a brush to remove any stains and odors.
How do you seal a kitchen sink to granite counters?
Granite counters don’t offer much more difficulty than other counters when it comes to sealing a kitchen sink. You can use the exact same methods as outlined in this guide to seal your sink to your granite countertop.
The one thing to remember when working with granite counters is to be very careful when removing old caulk with a razor blade. Stone counters like granite are much easier to scratch than others.
The caulk should be soft at this point, so it shouldn’t take too much force to scrape it away, but it’s still best to be cautious with your granite counters.
How do you caulk a kitchen sink drain?
Caulking a drain is not much different from caulking the edges of a sink. The biggest difference is that you have another option of sealant when it comes to drains: plumber’s putty.
Plumber’s putty is an oil-based clay compound that can be molded around your drain insert. It’s not an adhesive, so it doesn’t dry like caulk. If you ever need to replace the drain, plumber’s putty is easy to remove.
Silicone caulk offers stronger water resistance, but it is much more difficult to apply and remove.
If you’re using plumber’s putty, knead enough putty to wrap a ½” thick rope around the underside of your drain insert. Place the insert into its hole in the sink and apply pressure; wipe away any excess putty that presses out from the sides.
With plumber’s putty, your sink can be used immediately; there’s no need to wait as the putty isn’t affected by water.
If using silicone caulk, apply a bead of sealant around the underside of your drain insert and insert it into the drain hole; apply pressure and wipe away any excess caulk before it hardens.
As with the edges of the sink, you should wait 24 hours before using the sink drain after using caulk.
For both types of sealants, be sure to follow the manufacturer’s label for the best results.
Recaulking a kitchen sink is a useful maintenance skill for anyone to have. Whether you have granite countertops or a drop-in sink, we hope this guide has covered everything you need to know to keep your kitchen sink watertight for years to come.