How to Fix a Cracked Toilet tank

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Don’t you hate when a perfectly functioning toilet is spoiled by a nasty crack in the tank? Well, don’t worry! Fixing that crack doesn’t have to be an expensive plumber visit.

With a few essential tools and some easy-to-follow tips, you can have your restroom functioning properly in no time. In fact, repairing the toilet may even be more straightforward than figuring out how all those mysterious knobs and buttons work. With just a little elbow grease, you can soon have your restroom back in full working order in no time.

What Causes Toilet Tank Cracks

Interesting toilet in Miraflores - Lima Peru

Toilet tanks are incredibly sturdy, but an impact with a hard object or person can still cause tiny hairline fractures that expand over time. Due to production flaws or preexisting cracks that have gone unnoticed until now, these tanks may suddenly develop fissures.

Furthermore, high-pressure accidents and inadequate maintenance could be responsible for such cracking.

When Should You Repair A Cracked Tank

Deciding whether or not to repair a damaged toilet tank is complex and should be evaluated in light of several factors, such as its age, condition, where the fracture occurred, and how keen it is. If your fixture looks new and works properly aside from the crack, patching up the container will most likely serve you well.

Nonetheless, if the crack is considerable or situated in an area that’s hard to access, repairing it may be too expensive and complicated to make it worth your time. To keep track of splits above the waterline accurately, always measure them and indicate their growth with a line for future reference. This way you can decide whether further action is necessary.

How To Fix A Cracked Toilet Tank

Broken toilet lid

By using the right tools and materials, repairing a broken toilet tank can be a straightforward process.

Materials & Tools Needed

In order to properly clean and seal the crack, you will need the following items: a putty knife, epoxy sealant, towels or rags for wiping down the surface, and a bucket of water.


To kick off this process, first, begin by draining the toilet tank. Turning off the water and flushing it out of the tank is essential in order to ensure all traces of liquid are gone; since any moisture would delay sealant drying. Then dry out the exterior with a cloth or towel to prevent condensation buildup later.

To fix a crack in your toilet tank, start by filling the break with putty or epoxy. Then use a putty knife to create an even surface. Plumber’s putty is the go-to choice since it hardens more quickly yet remains somewhat malleable after drying. As such, be sure to follow the directions completely and wait a full 24 hours before using your toilet once again.

Ensure that no gaps or ruptures show up in the epoxy layer of your tank. If you notice any cracks, be sure to seal them with more layers of epoxy. Afterward, fill the tank back up with water and search for leaks around its seams to guarantee a successful repair experience. To guarantee a stress-free experience, have some towels on hand for extra precaution.

Frequently Asked Questions

How much does it cost to replace a toilet tank seal?

The cost of replacing a toilet tank seal will depend on various factors, such as the type of sealant used and the complexity of the repair process. In general, you can expect to pay between $60 and $200 for a professional repair service.

Can you seal a porcelain toilet tank?

Yes, it is possible to seal a porcelain toilet tank. However, the type of sealant that you use will depend on the nature of the crack or fracture in your tank. In some cases, you may need to use a specialized sealant designed specifically for porcelain in order to get the best results. Talk to a professional plumber for more advice and recommendations.

How do you fill a crack in a water tank?

To repair a crack in your water tank, utilize a putty knife to spread the sealant over the fracture. Give it time to dry and then test for leaking by refilling the vessel and examining if any cracks remain along its edges. This simple process should have you back up and running with no leaks.

Can you use Gorilla glue on porcelain?

Yes, Gorilla glue is a good choice for repairing cracks and fractures in porcelain fixtures, such as toilet tanks. However, it is important to make sure that you use high-quality, waterproof glue that will stand up to frequent moisture exposure.

What happens if the wax seal breaks on the toilet?

If the wax seal of your toilet is not properly sealed, you may experience water leakage issues. This can cause warping and weakens the floor beneath your bathroom tile, which could result in needing to replace the entire floor if left unattended for too long.

Can Flex Seal fix a cracked toilet tank?

Absolutely! Flex Seal is an ideal solution for a range of bathroom repair needs. It effectively forms a pliable, waterproof seal over any cracks or leaks in materials like porcelain and more to keep water out reliably.


Say goodbye to leaky toilets! With the help of a few tools and some simple steps, you can now repair any cracks or breaks in your toilet tank quickly and easily. Whether you opt for the DIY approach with a repair kit or call on an expert to assist, we guarantee that your restroom will soon be back in full working order.

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