Cracked in Fireclay Sink: How to Repair?

Fireclay sinks can be scratched. If you notice a crack, chip, or scratch in your fireclay sink, it’s essential to repair it. A crack in the sink can lead to a leak and ruin your floor, so it’s important to repair the crack as soon as possible.

There are a few quick and easy steps you can take to repair the cracked, chipped, or scratched sink. Apply a layer of caulk around the perimeter of the crack, then secure the caulk with a sealant. Make sure to wait two hours before removing the sealant, so that it has time to set. Finally, paint or stain the surface of the sink to cover up the sealant.

Can you fix a cracked fireclay sink? Yes, repairing a hairline crack in a porcelain sink can be done using a number of methods, and the choice ultimately depends on the severity of the crack.

In most cases, a standard repair using a sealant will suffice. However, if the crack is very big or numerous, then a more extensive repair may be required.

In this article, I’ll explore the steps you need to follow to repair cracks in the fireclay farmhouse sink.

How to Repair Crack in Fireclay Sink

How to Repair Crack in a Fireclay Sink

Most fireclay sink designs have a vintage and timeless theme. This type of farmhouse sink is also affordable, durable, and versatile.

Things you’ll Require:

  • 180-grit or 200-grit sandpaper
  • Tack cloth/lint-free cloth
  • Epoxy putty or Porc-A-Fix compound
  • Spatula/flat stick
  • Safety gloves

Step 1: Examining the Size of the Crack

Examining the size of the crack/damage helps you validate the necessary tools to use.

If the damage is extensive, you will require additional tools like the porcelain reinforcement kit and tile adhesive compound.


  • If the crack is extending to the faucet or close to the faucet, you should disassemble the faucet first.
  • If there is a massive crack in the sink, then you SHOULD NOT repair it. Instead, replace the entire fixture.
  • If the damage is slight, you should repair it immediately to avoid the crack extending and cutting across the entire sink’s surface.

Step 2: Cleaning the Sink

First, use hot water and dish soap to clean the sink’s surface thoroughly. Next, rinse the sink with enough water to expose the cracks. After the sink is dry, you will physically notice all the cracks that should be fixed.

Step 3: Sanding the Affected Spots

Gently scrub the sink surface using 180-grit sandpaper. Take precautions not to apply excess pressure and damage the rest of the surface. Use a tack cloth to get rid of the tinny fireclay and enamel particles from the surface of the sink after you finish sanding.

Step 4: Apply Epoxy or Porc-A-Fix Putty Along the Crack

Epoxy putty is a repair compound and a gap-filling solution for porcelain sinks and fireclay fixtures. This particular compound blends precisely with the surface of the sink to create a spotless finish.

  • Using a spatula, spread enough amount of epoxy putty along the crack to fill it.
  • Smooth the putty to create an even finish
  • Leave the putty to dry/cure naturally (this should take approximately an hour)

Remember: If the crack is still visible, reapply another coat of epoxy putty and let it dry naturally.

Step 5: Sanding the Sink after Repairing

Once you finish filling the crack, use the 180-grit or 200-grit sanding paper to smoothen the sink surface.

Step 6: Polish or Re-gloss the Sink Surface

Polishing or waxing the sink after you finish the repair is optional.

What Causes Crack in a Fireclay Sink?

Many different reasons can cause a fireclay sink to crack. Some of these reasons occur naturally, while others can be a result of human fault.

1. Over tightening of the Drain or Garbage Disposal Flange

Usually, when installing the garbage disposal flange, you tend to use a lot of effort to screw the flange into position.

If the flange is too tight, the fireclay sink will develop a crack from the drain hole and spread gradually.

2. Weak Sink Surface

If the sink was not fired to the standard temperatures during construction, its bonding compounds will not be resilient. After a while, the sink will develop a crack naturally after a slight change in temperature levels.

3. Excess Physical Pressure

You should not drop utensils or other accessories on the fireclay sink when preparing to wash. Fireclay sinks, just like ceramic sinks, chip when excess physical pressure is applied.

4. Unavoidable Accidents

Mostly during home renovations, homeowners tend to shift accessories from one location to the other. In this process, you can knock the sink over and cause it to either crack or break completely.

Cleaning the Farmhouse Sink After Cracks Repairing

Almost all fireclay sinks are resistant to staining and scratching. But you should note that these particular sinks have delicate skin. Additionally, the sink is the easiest sink to install, clean, and maintain.

But never use any abrasives to clean the sink – even for extensive cleaning. This is because most abrasives will scratch and damage the sink’s surface.

Always use a soft cloth and dish soap/mild cleaners.


  • Dishwashing compound or solvent cleaner
  • Baking soda
  • White Vinegar
  • Dish gloves
  1. Plug the sink
  2. Fill the sink halfway with boiling water. However, if the sink is stained, you can fill the sink up to the drain hole.
  3. Let the boiling water sit for approximately 30 minutes (until it cools to room temperature).

The boiling water helps in melting grease stuck on the sink’s surface from food particles.

  1. Unplug the sink and let it drain completely.
  2. Apply dishwashing soap/mild cleaners on the sink surface and scrub it gently with a soft cloth until it shines. Apply two parts baking soda and one part vinegar if stubborn stains are present on the sink’s surface.
  3. Rinse the sink with hot water and dry it with a soft cloth.
  4. Wax the farmhouse sink with a special waxing paste if it is extremely damaged or faded.

Remember: Regularly cleaning your fireclay sink ensures that it is spotless and free from bacteria. Also, AVOID scouring forms, steel wool, and concentrated drain cleaning solutions.

How to Repair a Scratched Fireclay Sink

Before you get into the do-it-yourself spirit, you need to collect the required materials. Here are what you need from start to finish.

  • Sponge or soft cloth
  • Soap
  • Abrasive cleaner or nylon scrub pad
  • Masking tape
  • Fireclay repair liquid

Inspect the Scratch

Before using any material on your fireclay sink, take some minutes to inspect the scratch. You may be surprised what you take as a scratch is a gray/black stain from pots and pans.

Apply some abrasive cleaner to the affected area and scrub thoroughly with a wet sponge/soft cloth. Now rinse with water to see if there are changes. If the mark remains, you’re definitely dealing with a scratch.

Clean the Sink

Now that you’ve confirmed what you are dealing with, it is time to clean the sink. Even if it is just a little scratch, you cannot repair a filthy sink. Following the same process in step one, clean both the sink walls and bottom.

However, if there is grime or buildups, you may need to use a nylon scrub pad instead. Cleaning the sink will help you see the scratch more clearly and plan where to start the repair.

Demarcate the Scratched Area

Before applying the fireclay repair liquid, it is preferable to demarcate the affected areas. So, fix masking tape around the places you are repairing. Now leave the sink to dry.

Apply Fireclay Repair Liquid

Shake the Fireclay Repair Liquid bottle and apply some to the scratched areas.

Ensure you use a repair liquid with the same color as your sink. Afterward, leave the sink to dry. Finally, rid the sink of excess fireclay repair liquid with a nylon scrub pad.

Final Verdict

Fireclay farmhouse sink is a great option for anyone looking for a durable and stylish sink. However, they can be prone to cracking if not installed and used properly.

By following the guidelines described in this blog, you can keep your farmhouse sink in good condition and avoid any unnecessary repairs.

Do you have any questions about repairing a fireclay farmhouse sink that is cracked or scratched? Leave a comment below and I’ll be happy to help you out.

Lisa Burks

Hi, I'm Lisa Burks, founder of the Sink Formula blog, and plumber of 5 years experience.

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