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Common Questions

  1. How do I repair Cracks in Tile? - Tiles are cracked for the 2nd time in the bathroom. The concrete below is cracked. Other tiles are cracking more and more in the house. Need to know what to do to prevent and repair damage.
  2. Is the cold Cracking the Tile - I layed down a floor and ceramic tiled it around the door. From the cold the tile keeps cracking. How can I fix this problem?
  3. Cracked Grout Joints - I just had tile installed and I live in a raised house. I had family members say they knew how to install and didn't think into it much but I think they did it wrong. We put it in the kitchen and we got the wonder board that is cement about half inch thick (we bought the thicker stuff at home depot) and we got the thin set stuff and the grout. Now the grout is cracking (looks like only in the spots where the wonderboard meets) I really hope we didn't screw this up too much because we already installed cabinets over the tile. Is there anything we can do about this? I think they left a gap at the corners but we never went back to fill the gaps in the corners so I hope that has nothing to do with it.
  4. Cracks in Grout - I RESENTLY HAD CERAMIC TILE INSTALLED AND I NOW HAVE THE GROUT BREAKING AWAY IN PIECES AROUND SOME TILES.I ALSO HAVE ALOT OF FINE CRACKS IN THE GROUT.WHAT IS THE PROBLEM AND HOW CAN I FIX IT?
  5. Cracking Tile - I have a ceramic floor that is cracking I think I did everything right but I am not sure I fixed the problem. PLEASE HELP ME THANK YOU
  6. Subfloor Cracks - What can I do to prevent cracks in subfloor to continue through my ceramic tile or stone?
  7. Crack in Tub to Wall Sealant Joint - My wife & I hired a very reputable company to do a full bathroom remodel, which was just completed about a month ago. The tiles on the wall look great but a problem that we are now seeing is that there is a very noticeable larger than hairline crack running through the middle of the sealant around the bathtub where it meets the wall. The first time we saw this was when the tub was filled with water. We then called back the grouting person who redid the job and this time with the tub full - we also left the tub filled for a few days after that to let the sealant properly dry. Nonetheless, after a few days of use, the cracks reappeared - although they are mostly visible only when the tub is full or when a person is standing or sitting in it. Our new tub is a standard acrylic (fiberglass?) model and the contractor is telling us that the give we are seeing is to be expected and we will need to do regular regrouting every few months. We have asked around about the problem and are receiving conflicting information ranging from "it's normal with this type of tub" to "it's a structural problem with how the tub is seated". What we would really like is for an unbiased qualified inspector to come in and take a look and give us a proper diagnosis. We live in the Pasadena/Los Angeles, California area and we were wondering if your organization can either offer or recommend a service that might be able to help us out with arranging an inspection. Thanks very much and any further info is greatly appreciated,
  8. Cracks in Concrete Substrate - I have purchased 2800 sq feet of travertine tile to install in a remodeled 30 year old home. Just recently I learned that the cement has large areas that have settled unevenly as the house is 25 yeas old. The settling is normal but there appears to be many oleander roots under, in and around the foundation, and it appears possible that they may be responsible for some of the shifting. Can we still lay our travertine throughout the house and what is the best subfloor to set the tile to prevent cracking from possible future movement? Thanks for your advise.
  9. Cracks in Concrete Slab - I plan on having 18" porcelain tile installed in my home over a concrete slab foundation. There are miner cracks in the foundation. I was told that the cracks will not cause my tile to crack because my house is 17 years old, and therefore, is through setteling. What is your opinion?

How do I repair Cracks in Tile? - Tiles are cracked for the 2nd time in the bathroom. The concrete below is cracked. Other tiles are cracking more and more in the house. Need to know what to do to prevent and repair damage.

ANSWER - If there are cracks in the concrete substrate to which your tile is attached and after replacing the tile they cracked again, and you have other tiles cracking throughout the house then either the cracks are structural in nature (move vertically) or are shrinkage cracks that move within the horizontal plane for the concrete slab.

Tile should not crack if installed correctly.  Tile should not be installed over a concrete floor that has cracks without repairing them or isolating them first.  If you have structural cracks that is normally due to settling within the ground for on-grade slabs or due to too much deflection in suspended slabs, then the cracks and the conditions that caused them have to repaired according to a structural engineer.

If the cracks are common shrinkage cracks then those cracks have to be isolated with a crack isolation membrane.  This is normally a sheet, liquid or trowel able membrane designed for tile installations.  You can isolate an individual crack by applying it over the crack the span of approximately 3 times the within the tile you are using so the tile is completely bonded to the membrane that is bridging the crack.  To prevent future cracking or to isolate large areas of cracking then the crack isolation membrane should cover the entire area.

For your situation, assuming they are shrinkage cracks that were never isolated, and there are a limited number of cracked tiles, I would replace those cracked tiles and apply the crack isolation membrane under the entire tile that you replace.  For a list of manufacturers who produce crack isolation membranes and other tile installation products, go to our website at www.CTaSC.com and go to the resource and links page and to installation products for a list of manufacturers with links to their websites.  Good luck.
 


Updated: June 27th 2010


Is the cold Cracking the Tile - I layed down a floor and ceramic tiled it around the door. From the cold the tile keeps cracking. How can I fix this problem?

ANSWER - Cold weather should not cause ceramic tile to crack particularly if it is an interior application.  It is possible that if you have a very porous ceramic tile that you have installed outdoors for an exterior application and it is subjected to wetness and freezing then you might get some cracking or spalling within the tile.

Chances are you have other deficiencies in your tile installation.  Generally speaking when there is a problem there are compounding factors or deficiencies that have resulted in the problem.  Cracking can result from several different common conditions. 

Over a concrete slab if the slab is cracked then that crack can telegraph up through the tile.  Shrinkage cracks can be isolated with a crack isolation membrane.  Structural cracks (has vertical movement) requires a special repair. 

Wood subfloors can have too much deflection that can cause cracking in tiles.  The floor can't have more deflection than L/360, so in other words you should not be able to feel the floor bounce when you jump up and down.  If there is a backer board or wood underlayment applied on the wood subfloor and it isn't installed correctly then the movement within the joints of the board panels can cause cracking in the tile above it.

If the tile was not bonded (attached) well to its substrate then that could cause the tile to come loose and then be subject to cracking as it is traveled over.

If you have not installed movement joints (expansion joints) at the perimeters and throughout the floor then that could further contribute to the tile cracking.

Chances are your problem involves more than one of these factors and together they result in your tile cracking.

Depending on the deficiencies you might be able to do repairs or you may need to replace the floor.  For a copy of the CTaSC installation guidelines for ceramic tile or stone go to the FAQ section under Installations, or click "CTaSCinstallationGuidelines".  Good Luck.
 


Updated: January 30th 2010


Cracked Grout Joints - I just had tile installed and I live in a raised house. I had family members say they knew how to install and didn't think into it much but I think they did it wrong. We put it in the kitchen and we got the wonder board that is cement about half inch thick (we bought the thicker stuff at home depot) and we got the thin set stuff and the grout. Now the grout is cracking (looks like only in the spots where the wonderboard meets) I really hope we didn't screw this up too much because we already installed cabinets over the tile. Is there anything we can do about this? I think they left a gap at the corners but we never went back to fill the gaps in the corners so I hope that has nothing to do with it.

ANSWER - It is hard to make any definitive conclusions without inspecting your floor thoroughly.  When there is a problem it is normally not for one single thing that has gone wrong, but for compounding reasons.  I would guess that the problem is the subfloor may not be adequately supported and may have too much deflection within it.  Plus the Wonder Board Cementitious Backer Board (CBU) is probably not properly installed.  It should be nailed every 6" to 8" with the proper fasteners, and each board placed in a staggered position to the adjacent board.  The joints of the board filled with thin-set.  Since it is likely cracking at the CBU joints all of those conditions could contribute to that problem.  Since the grout is cracking and not the tile, then hopefully the tile is substantially attached to the floor. 

The only way to properly fix the problem is to remove, repair, and replace.  Although since only the grout is cracking, you can try to fix the symptom of the problem, but there is no guarantee it will work.  Just replace the cracked grout with a pure silicone or urethane sealant in a complementary color that meets ASTM C920 and has a Shore A hardness of 35 or greater.  Do not use one of those latex or acrylic caulking, because it won't last.  Make sure you read the instructions on the sealant.  Remove the grout and clean the joint thoroughly, and then put masking tape along the tile edges.  Fill the joint with sealant, tool it, and pull the tape right away.   Good Luck.


Updated: September 21st 2009


Cracks in Grout - I RESENTLY HAD CERAMIC TILE INSTALLED AND I NOW HAVE THE GROUT BREAKING AWAY IN PIECES AROUND SOME TILES.I ALSO HAVE ALOT OF FINE CRACKS IN THE GROUT.WHAT IS THE PROBLEM AND HOW CAN I FIX IT?

ANSWER - Cracking grout is a symptom that there is excessive movement in the tile.  The excessive movement could be caused by too much deflection within the floor.  The industry standard is that the deflection of a floor should not exceed 1/360.  If the tiles are not attached properly and are hollow that could also cause the cracking grout too.  The first thing to do is determine what the problem is and then you will be able to determine the remediation options to repair the floor.  CTaSC does provide installation failure inspections throughout the USA.  Please visit Installation Failures for more information on the www.CTaSC.com website by click here: Installation Failures.

 

Good Luck!


Updated: October 29th 2008


Cracking Tile - I have a ceramic floor that is cracking I think I did everything right but I am not sure I fixed the problem. PLEASE HELP ME THANK YOU
First you need to determine why the floor is cracking. It could be that the concrete subfloor has a crack in it that is continuing up through the ceramic tile. It could be that the subfloor you installed the tile on to has too much deflection beyond the limits of the ceramic tile. Normally you will see the cracking occurring first in the grout joints which is normally the weakest link of the floor. It could be that you have voids under the ceramic tile and as point loading forces are applied to those areas there is nothing supporting the tile and it cracks. It is common to see this problem at the corners of ceramic tile or stone.

Each one of these conditions have a variety of symptom and you would have to do a trouble shooting investigation to determine through a process of trial and error. In some cases you may need to do intrusive testing to determine the most likely cause of the cracking.

Once you determine the cause, then that will dictate the solution.

Good luck!


Updated: September 23rd 2008


Subfloor Cracks - What can I do to prevent cracks in subfloor to continue through my ceramic tile or stone?

ANSWER - To keep it simple, there are two basic types of cracks. A structural crack that moves vertically or a shrinkage crack that moves horizontally. You can not treat a structural crack. You either intentionally continue it up through the ceramic tile or stone or there has to be a major epoxy repair with dowel pins. You need an engineer to prescribe the solution. You can treat a shrinkage crack by installing an anti-fracture membrane (also referred to as crack suppression membrane). The membranes are available in several forms which are trowelable, liquid applied, peel and stick, or a sheet membrane. There are several quality products on the market, so contact your local distributor to give you a recommendation. For links to installation manufactuers go to Industry Resources and Links section of this web site. Check the manufacturer's warranty to make sure you comply! The way they work is that you attach the membrane to the concrete substrate. Either isolating the individual cracks by centering and covering at least three times the width of the tile you are using. Or by covering the whole substrate to have protection in case cracks develop later. Then you thin-set your tile to the membrane. Be sure to follow manufacturer's instructions.


Updated: September 23rd 2008


Crack in Tub to Wall Sealant Joint - My wife & I hired a very reputable company to do a full bathroom remodel, which was just completed about a month ago. The tiles on the wall look great but a problem that we are now seeing is that there is a very noticeable larger than hairline crack running through the middle of the sealant around the bathtub where it meets the wall. The first time we saw this was when the tub was filled with water. We then called back the grouting person who redid the job and this time with the tub full - we also left the tub filled for a few days after that to let the sealant properly dry. Nonetheless, after a few days of use, the cracks reappeared - although they are mostly visible only when the tub is full or when a person is standing or sitting in it. Our new tub is a standard acrylic (fiberglass?) model and the contractor is telling us that the give we are seeing is to be expected and we will need to do regular regrouting every few months. We have asked around about the problem and are receiving conflicting information ranging from "it's normal with this type of tub" to "it's a structural problem with how the tub is seated". What we would really like is for an unbiased qualified inspector to come in and take a look and give us a proper diagnosis. We live in the Pasadena/Los Angeles, California area and we were wondering if your organization can either offer or recommend a service that might be able to help us out with arranging an inspection. Thanks very much and any further info is greatly appreciated,

ANSWER - It is not normal for that joint between the tub and the wall to crack and it should not have to be redone on a regular basis.  There could be a few things wrong. 

First is the installer probably used the wrong type of sealant.  Commonly installers use a latex based sealant that is easy for them to use and will not last.  The manufacturer of these types of latex or acrylic sealants will not warrant them for lasting.  The proper type of sealant that is required per the tile industry standards is one that meets ASTM C920, which is normally a 100% silicone structural sealant or a urethane sealant.  These types of sealants will last many years and the manufacturers warrant them.

Second is that the joint width of this transition joint should be at least 1/8” wide and ¼” deep so the sealant can adequately fill the joint and so there is enough sealant to allow it to elongate with the movement of the joint.  There needs to be a proper foam polyethylene bond breaker backer rod embedded into the joint before the sealant so there is only two point contact to further allow the sealant to maximize its elongation during movements.

Third is that the tub needs to be properly installed and supported so that it doesn’t move excessively.

We can and would be happy to perform an inspection with one of our local inspectors, but it might be cost prohibitive for this type of a problem.  Please go to our website at www.CTaSC.com to make a request for service for a cost estimate to perform an inspection.


Updated: January 22nd 2007


Cracks in Concrete Substrate - I have purchased 2800 sq feet of travertine tile to install in a remodeled 30 year old home. Just recently I learned that the cement has large areas that have settled unevenly as the house is 25 yeas old. The settling is normal but there appears to be many oleander roots under, in and around the foundation, and it appears possible that they may be responsible for some of the shifting. Can we still lay our travertine throughout the house and what is the best subfloor to set the tile to prevent cracking from possible future movement? Thanks for your advise.

ANSWER - You can not install your travertine or any type of tile over a concrete foundation that has cracks without first fixing the problem.

 

If it is simply shrinkage cracks that only move horizontally then there are a variety of installation systems that can be installed over it using a Crack Isolation membrane.

 

If the crack is a structural crack that will move up and down then the membrane will not work.  The concrete foundation would first have to be repaired.

 

I suspect from your message that you may have structural cracks and you need to remove the roots and stabilize the concrete.  You need to have your situation fully evaluated before your proceed.

 

As consultants we do evaluate potential installations and provide written architectural installation specifications and quality control services for an hourly fee.

 

There are many good installation systems, but there is one called Schluter Uncoupling system that works well with troubled floors, but it too is not recommended for going over structural cracks.  For the website addresses of the manufacturers of installation products go to our websites Resources and Links at ResourcesLinksInstallation.


Updated: January 22nd 2007


Cracks in Concrete Slab - I plan on having 18" porcelain tile installed in my home over a concrete slab foundation. There are miner cracks in the foundation. I was told that the cracks will not cause my tile to crack because my house is 17 years old, and therefore, is through setteling. What is your opinion?

ANSWER - Per our industry standards for ceramic tile and stone and from a practical point-of-view, any concrete substrate that has shrinkage cracks should be isolated with a crack isolation membrane.

If the cracks are structural cracks where there is a height difference from one side of the crack to the other then the crack isolation membrane will not provide protection and the crack will have be repaired with epoxy and dowel pins.

Shrinkage cracks will continually move in a horizontal plane and need isolating so they will not continue up through the tile.

Be sure to adequately place movement joints (expansion/soft joints) throughout the tile floor and along the perimeter where it abuts restraining walls. They should be placed every 20' to 25' each direction interior and for exterior or near interior windows and skylights every 8' to 12' in each direction. Use a proper sealant meeting ASTM C920 i.e. 100% silicone, urethane or polysulfide (not a latex caulking).

For website links to manufacturers of installation systems to go our website Resources and Links section under installation products


Updated: January 22nd 2007

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