Neuse Tile Service

Tile installation and service tips from professional installers

Why is my tile cracking?

5 Comments

     Properly installed tile doesn’t do much moving on its own, so when a tiled surface is cracking, there’s often an underlying problem. A recent article by Katelyn Simpson of the Tile Council of North America gives us some insight:
     In an installation over a concrete subfloor, reflective cracks can result from movement or cracking of the concrete. Concrete continues to shrink long after it’s first poured, and “it causes many shear and compressive forces on the thin-set, tile, and grout. If the shear force exceeds the strength of the bond, the tile may de-bond from the floor. This is also called tenting.”
To help prevent the problem?
       Allow concrete to cure so that any cracks that form can be filled and any distortion of the slab can be ground down. A cure time of 14 to 28 days may be sufficient depending on the thin-set adhesive to be used. Crack isolation or anti-fracture membranes can also be of help. These membranes bond to the concrete subfloor, and then the tile is installed with thin-set over top of the membrane. This can reduce any concrete movement from being transferred to the tile.
     The addition of movement joints can also diminish the stress that occurs between the concrete substrate and the tile. Of course, all floor tile installations should make allowances for movement.
     In an installation over wood, a possible cause for cracked tile is excessive deflection (lack of rigidity or excessive ‘bounce’). Typically, the grout will crack first, and in severe cases, the tile can crack as the compressive and tensile forces bear on the installation.
To help prevent the problem?
     Appropriate joist spacing can minimize deflection. This information from the TCNA information page sheds more light:
            “Traditionally, the accepted minimum requirement for floor rigidity is L/360 – before the tile underlayment is installed. The L/360 standard means that the floor should not deflect more than the “span” divided by 360. If the span of the joists is 10 feet (between supports), then the deflection should not be more than 1/3″ between the center and the end. Frequently, there is misunderstanding regarding deflection between joists. For example, while joist manufacturers regularly meet the standard L/360 criteria for code construction with 24″ on center systems, these floors often have deflection between the joists exceeding L/360.
      Recent research has shown tile to fail under some conditions, when the floor is more rigid than L/360 – in fact failures at L/600 have been observed. It is for this reason that recommendations for floor rigidity are not based on deflection measurements but on empirically established methods found to work over normal code construction.”
Neuse Tile‘s staff can provide consulting and repair services if you have a problem with cracked tile.

Author: Neuse Tile Service

We are second generation owners of a North Carolina business dedicated to quality tile and stone installations. Since 1964, the Neuse Tile team has worked very hard to maintain the quality and integrity that have been crucial to our business' success in the Triangle area. Specialty construction trades have changed and evolved over the years, and our certified installers are truly talented craftsmen. We are proud of our work, and are committed to doing everything we can to promote the proper installation of ceramic tile, to satisfy our customers, and to run a viable business. We are honored by the trust our customers place in us and look forward to serving this area with high quality tile installations for many years to come.

5 thoughts on “Why is my tile cracking?

  1. Very informative. I will be able to use this information when discussing tile issues with my clients.

  2. I’ve been having a similar problem with my tile. I had tile installed just a few months ago and I’m already seeing cracks forming in it. You made a very interesting point about adding movement joints. I didn’t know that it can prevent tile from cracking by reducing stress that occurs between the concrete substrate and the tile. Perhaps I should have thought to add movement joints before I had my tile installed.

  3. Thanks for reading! Yes, movement joints are an essential part of a tile installation. Next time, try finding a Ceramic Tile Education Foundation certified contractor in your area. They should be able to help with that, http://www.tilecareer.com

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s