How To Fix A Cracked Toilet Tank

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How to fix a cracked toilet tank – When your toilet tank cracks, it can be a major inconvenience. Not only is it unsightly, but it can also lead to leaks and other problems. Fortunately, fixing a cracked toilet tank is a relatively simple and inexpensive repair that you can do yourself with a few basic tools and materials.

In this guide, we will walk you through the step-by-step process of how to fix a cracked toilet tank. We will also provide tips on how to prevent future cracks and discuss alternative solutions if the crack is too severe to repair.

Identifying the Crack

How to fix a cracked toilet tank

A cracked toilet tank can cause a range of problems, from annoying drips to major leaks. Fortunately, identifying a cracked tank is usually fairly straightforward.

The most common sign of a cracked toilet tank is a leak. The leak may be small and only occur when the tank is full, or it may be a large leak that causes water to constantly drip or run.

If you notice a leak coming from your toilet tank, it’s important to check for cracks immediately.

Another sign of a cracked toilet tank is a change in the water level. If the water level in the tank is lower than usual, it may be a sign that there is a crack in the tank that is allowing water to leak out.

Conversely, if the water level is higher than usual, it may be a sign that the crack is preventing the tank from filling properly.

If you suspect that your toilet tank is cracked, there are a few things you can do to locate the exact location of the crack.

Visual Inspection

The first step is to visually inspect the tank for any cracks. Look for any lines or breaks in the surface of the tank, as well as any areas where water is leaking out.

Sound Test

Another way to locate a crack in a toilet tank is to listen for a sound test. Fill the tank with water and then listen for any hissing or dripping sounds. The sound of water leaking out of a crack can be very faint, so you may need to listen closely.

Potential Causes

There are a number of potential causes of a cracked toilet tank, including:

  • Impact damage
  • Thermal stress
  • Manufacturing defects
  • Age and wear

Repairing the Crack

Repairing a cracked toilet tank involves sealing the crack using epoxy or other sealant materials. The process requires careful preparation and execution to ensure a durable and effective repair.

Materials and Tools Required

  • Epoxy or sealant specifically designed for porcelain or ceramic repair
  • Sandpaper (fine-grit)
  • Cleaning solution (e.g., rubbing alcohol)
  • Clean cloths or paper towels
  • Mixing tools (e.g., disposable cups, mixing sticks)
  • Optional: Masking tape

Safety Precautions

Before starting the repair, ensure the following safety precautions:

  • Wear gloves and eye protection.
  • Work in a well-ventilated area.
  • Follow the manufacturer’s instructions for the epoxy or sealant.
  • Allow the repair to cure completely before using the toilet.

Preventing Future Cracks

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To prevent future cracks in the toilet tank, it is crucial to identify the common contributing factors and take preventive measures. Regular inspection and maintenance are also essential to maintain the integrity of the toilet tank.

Common Contributing Factors

* Overtightening the bolts:Excessive force when tightening the bolts that secure the tank to the bowl can create stress points and lead to cracks.

Uneven support

If the toilet is not level or the tank is not properly supported, it can cause uneven pressure and strain on the tank, increasing the risk of cracks.

Impact or excessive weight

Direct impact or placing heavy objects on the tank can cause immediate cracks or weaken the material, making it more susceptible to future cracks.

Harsh chemicals

Using abrasive cleaners or strong chemicals can damage the glaze and weaken the porcelain, making it more prone to cracking.

Extreme temperature changes

Rapid temperature fluctuations, such as pouring hot water into a cold tank, can cause thermal stress and lead to cracks.

Preventive Measures

* Tighten bolts correctly:Use the recommended torque and avoid overtightening the bolts that connect the tank to the bowl.

Ensure even support

Level the toilet and use a toilet tank shim kit to provide additional support and distribute weight evenly.

Avoid impact and excessive weight

Protect the tank from accidental impacts and avoid placing heavy objects on top of it.

Use gentle cleaning methods

Clean the tank with mild, non-abrasive cleaners and avoid using harsh chemicals.

Moderate temperature changes

Allow the tank to warm up gradually before pouring hot water into it.

Maintenance Schedule

* Regular inspection:Inspect the tank for any cracks or damage every 6 months or annually.

Tighten bolts

Check the tightness of the bolts that secure the tank to the bowl periodically and tighten them if necessary.

Clean the tank

Clean the tank with a mild cleaner and a soft brush to remove any buildup or debris that could weaken the porcelain.

Alternative Solutions: How To Fix A Cracked Toilet Tank

How to fix a cracked toilet tank

In certain situations, repairing a cracked toilet tank may not be the most suitable option. Here are some alternative solutions to consider:

Replacing the Toilet Tank, How to fix a cracked toilet tank

Replacing the toilet tank involves removing the old tank and installing a new one. This solution is recommended when the crack is severe or the tank is old and worn out. Pros:

  • Permanent solution to the problem
  • No risk of the crack worsening over time
  • May improve the overall appearance of the toilet


  • Can be more expensive than repairing the crack
  • Requires some plumbing skills or professional assistance
  • May require additional time and effort

Hiring a Professional Plumber

Hiring a professional plumber is an excellent option if you are not comfortable repairing the crack yourself or if the crack is complex. A plumber will have the necessary tools and expertise to fix the crack effectively and safely. Pros:

  • Ensures a professional repair
  • No need for any DIY skills or effort
  • Peace of mind knowing the crack is fixed properly


  • Can be more expensive than repairing the crack yourself
  • May require scheduling an appointment and waiting for the plumber’s availability
  • May not be necessary for minor cracks

When to Consider Replacing vs. Repairing

The decision of whether to replace or repair the toilet tank depends on several factors, including:

Severity of the crack

If the crack is small and superficial, repairing it may be sufficient. However, if the crack is large or deep, replacing the tank is recommended.

Age of the toilet

If the toilet is old and worn out, replacing the tank may be a more cost-effective option in the long run.

Your DIY skills

If you are confident in your DIY skills and have the necessary tools, repairing the crack yourself may be a viable option. Otherwise, hiring a professional plumber is recommended.