Why Do Tiles Crack in the Bathroom?

Request a Quote

Cracked bathroom tiles are a bummer for many homeowners. Aside from the cracks ruining the aesthetic of the bathroom design, they’re also a cause of concern that should be fixed immediately. But instead of simply slapping a filler onto the cracks, it’s crucial to find out the cause of the cracks first to see if it’s an indicator of a much bigger problem.

So why do the tiles in the bathroom crack? Tiles are the best option for bathrooms because they’re low-cost, durable, and moisture resistant. The material might crack because of a sharp blow, heavy load, spaced joists, control joint installation, problems with the concrete substrate, wrong use of adhesive, and low-quality tile.

6 Possible Reasons Why Bathroom Tiles Crack

Ceramic tiles are the primary choice for kitchens and bathrooms because of their excellent moisture resistance. They’re also low-cost and easy to maintain. However, this material is susceptible to cracks as time passes. This causes homeowners to spend around $185 to $425 to fix the tiles in their homes and prevent the cracks from developing again.

But by learning about the possible reasons why tiles crack, homeowners avoid the unfortunate situation. It also saves them a lot of cash that’s otherwise spent on finding the right flooring material and paying the contractor to install new ones. Preventing the tiles from cracking also helps maintain the stability of the building’s foundation.

Here are six of the most common reasons why bathroom ceramic tiles crack:

1. Sharp Blow or Heavy Load

Check the crack on the tile if it only extends on one tile. This usually happens when there is a sharp blow on the tile’s surface. It even leaves some chipped-off parts in the spot where the sharp blow hit.

Another possible reason is the presence of a heavy load on one part of the bathroom. Tile manufacturers are required to comply with the ASTM C648 Breaking Strength standards. This means that the ceramic tiles should withstand around 250 lbs. of pressure. Some specialty tiles have higher breaking points up to 400 lbs.

2. Improperly Spaced Joists

Joists refer to the beams under the subfloor. They keep everything anchored in place. Having huge gaps between two joints allows the plywood to flex too much. This eventually leads to instability of the structure that causes the tiles above to crack.

The joist spacing should follow the International Residential Code to avoid too much deflection in the plywood. Adding more underlayment structures also help with restricting the flex to avoid the tiles from cracking.

3. Control Joint Installation

Control joints are applied on concrete slabs to control future cracks that might develop. They’re used to relieve the stress and movements due to shrinkage or swelling in concrete or masonry. These preplanned cracks are placed in strategic areas of the flooring to purposely create weak areas.

However, installing tiles over a concrete slab that has control joints isn’t a wise choice. There’s a huge chance that the concrete slab takes advantage of the control joint, which results in cracked tiles.

4. Problems with Concrete Substrate

The state of the concrete substrate also affects the tiles. Here are two kinds of problems that homeowners might encounter with their concrete substrate that results in damaged tiles in the bathroom:


New concrete poured over a home goes through a process called “curing.” During this time, the material evaporates excess water and shrinks. Concrete curing is a dynamic process that helps the aggregates in the mixture bond together tightly. Installing the tiles before the concrete has fully cured stresses the flooring and causes it to develop hairline cracks.

According to the Tile Council of America, the concrete should be left alone to cure for 28 days before the installation of flooring materials. Other manufacturers argue that it should only take 14 days, but it’s better to wait longer to avoid unwanted cracks on the bathroom tiles.


It’s common for concrete floors to develop cracks over time. But concrete is still considered the best substrate for tiles despite having this problem. When the concrete starts cracking, the movement passes onto the tiles above. This results in a reflective crack on the surface of the bathroom tiles.

The best way to determine if the cracked substrate caused the tiles to crack is to observe the formation of the cracks. Long cracks that extend onto multiple tiles are indicators of the cracked concrete substrate below it.

The best solution for this problem is to install a crack isolation membrane before replacing the tiles. This membrane separates the movement of the tiles and the concrete substrate to prevent reflective cracks from forming.

5. Wrong Adhesive Used

Finding the right type of tile adhesive is also important to avoid cracks from forming. If the wrong adhesive is used, the tiles won’t properly stick to the subfloors. Without the right support to hold it in place, the tile becomes more susceptible to large cracks.

6. Low-Quality Tile

The tiles are the only visible parts of the installed floors, which is why most homeowners assume that the tiles are at fault. While this is not the case most of the time, there’s also a possibility that the contractor only installed sub-standard tiles for the bathroom.

Prevent this mishap by checking the specifications of the tiles before buying them in bulk. Purchase tiles from trusted retail lines like home improvement stores or trusted online outlets. It assures you that the tiles were manufactured according to the ANSI and ASTM standards.

Are Cracked Bathroom Tiles a Problem?

Shower and floors done in Tile at local senior home

Once the cracks on the bathroom tiles have been discovered, it’s important to fix or replace them quickly to prevent further damage. The seeps into the floor and bathtub tiles, which eventually affects the integrity of the house’s foundation. It’s also likely that homeowners have moisture problems in parts of their homes where water shouldn’t be found.

Molds, mildew, and other harmful organisms might also take refuge with the broken tiles where water has already seeped in. This forces homeowners to get mold treatments for their home, which incurs more unnecessary costs that could’ve been prevented with quick tile repair or replacement.

How to Prevent Shower Tiles from Cracking

Like most problems, it’s also better to prevent the tile cracks than fix them. Here are a few tips to follow to prevent cracks from developing on the bathroom tiles:

  • Ensure that the high-quality tiles for the bathroom floors and walls were bought from a trusted provider.
  • Find the right type of tiles that withstand different moisture and heat levels. If you prefer taking a steam shower, remember that ceramic tiles crack when exposed to prolonged heating.
  • The tiles must be installed using the right materials.
  • Use a crack isolation membrane to prevent reflective cracks.
  • Check if the right adhesive is used to stick the tiles onto the subfloor.
  • Let a professional flooring contractor handle the job instead of installing the tiles by yourself.

How to Fix Cracked Shower Tiles

If there are only tiny or hairline cracks on the bathroom tiles, it’s easy to fix them using some filler and paint. Here are a few steps to follow when fixing the cracked shower tiles:

  • Clean the tiles first before starting anything. Soap and water are enough to remove the gunk, dust, and dirt on the bathroom floors, but make sure to rinse them well.
  • Dry off the cracked tiles with a towel to prevent the soap from mixing with the filler. Also, make sure to dry the inside of the crack by waiting for a few minutes or drying it with a hairdryer.
  • Mix the paint with putty until the right color is achieved. Store-bought kits usually have detailed directions and color matching charts to guide homeowners on how to use the product correctly.
  • Apply the mixture onto the crack using the spatula. Remove the excess putty and wait for it to dry.
  • Seal the filler using a sealant after it has fully dried.
  • Wait for at least 48 steps for the filler and sealant to cure before stepping into the tiles again.

When to Replace Bathroom Tiles

It’s better to replace the bathroom tiles when the cracks are too large or there are numerous cracks in a single tile. The first thing to do is to break up the tiles using a hammer. A chisel is also useful for removing the adhesive and picking the tiles up.

After discarding the broken tiles and cleaning up the area, it’s time to prepare the replacement tiles. Spread the right amount of adhesive onto the back of the new tile and place it on the empty spot in the bathroom. Wait for the adhesive to dry completely before filling the edges with fresh grout. When the grout has dried, wipe the new tiles with a damp cloth to clean up.

High-Quality Flooring Materials and Installation by Zothex Flooring

We all want our bathrooms to be attractive and safe to use but having cracks on the walls, floors, and bathtub is never a good sign. Whether the fault comes from sloppy installation or low-quality materials, fixing the cracked bathroom tiles should be done immediately before it leads to further damage.

Here at Zothex Flooring, clients don’t need to worry about cracked tiles in their bathrooms thanks to our superior installation services and high-quality bathroom tiles. Take your pick here at Zothex Flooring by calling us at (916) 925 - 1958 or visiting our website.

Learn more: Glue Down or Floating Floor: Which Flooring Option is Better for My House?

Related Posts

Top magnifiercross