# Ceramic Tile Bucking Up?



## honeebee52 (Jan 14, 2006)

Hello, 
I am new to this forum but thought ya'll might be able to help me with some suggestions and/or answers!  We put ceramic tile down in our living, dining, kitchen, hall area about 5 years ago and really love it!  Last year, one section, about a 3x3 square just seemed to rise up from the foundation. It did not seperate but you could tell there was a rise from the floor.  Now, more have become loose.  We are begining to take up the loose tiles and have been told there may have been a crack in the foundation.  We have taken up about a 3x15 tile rectangle and have not seen a crack yet. We have lived here 28 years so our foundation should have been settled(?).  Does anyone have any suggestions as to how to prevent this?  I certainly don't want to replace this and have to do it again!  Any help or suggesiton will be GREATLY appreciated!
Thanks,
Betty


----------



## honeebee52 (Jan 14, 2006)

Anyone there familiar with Ceramic Tile? As I sit here, my husband is removing some of the loose tile. Now, I hear pops all over the room!!  
The tile is becoming loose in several places!  Helpppp. Anyone?


----------



## Square Eye (Jan 14, 2006)

Do you have concrete floors?


----------



## honeebee52 (Jan 14, 2006)

Yes, concrete is the foundation. We have looked the concrete over with a magnifying glass for a crack and have found none.  The company where we purchased our tile suggested that the cause was either a crack in the concrete foundation or a water leak.  So far all of the concrete flooring has been as dry as the desert~!  Any ideas?  I am afraid that my entire house is going to buck up and crack!  Thanks again!
Betty


----------



## TxBuilder (Jan 14, 2006)

Sounds like foundation problems. The crack in the foundation might not have reached the surface for it to be visble.

What are the details on your house? Location, foundation, etc.


----------



## Square Eye (Jan 14, 2006)

Tx is right, you'd be surprised how much a slab can flex before it cracks. If there are any large trees near your house you could have a big old root pushing up on the floor. I was under my house last summer and was horrified when I found a root bigger than my leg that had come up out of the ground. It's exposed for about 18 to 20 ft. In the spring I'll have to rent a trencher and cut it off. Also, a sink-hole under a slab is a nightmare in it's self. People covered old wells with wood and rock years ago and they've been falling through ever since. Maybe you just have a little heaving and some tile replacement will fix your problems for another 5 to 10 years.

Good luck Betty,
Tom


----------



## honeebee52 (Jan 15, 2006)

Sorry, been away form the computer for a bit.  Our home is on a hill, sandy soil.  No large trees nearby.  One problem we do have is moles!  Those pesky little things are constantly digging underground.  We have tries every thing we could think of for the last 10 years to get rid of them.  Would it be possible for them to tunnel under the foundation? Or would their tunneling in the yard cause the house to move? However the only tile bucking up is in the living area, no water lines in that part of the house.  When we went to bed last night we heard another pop like a rifle shot!  More tile! ugh!  Would anyone suggest replacing the tile or would you use another type flooring?  I live in North LA. I have considered staining my concret foundation. I really hate to replace the tile and have it buck again, in a day, month, year, or even years.  I appreciate all of your comments and suggestions!   Thanks again!
Betty


----------



## Square Eye (Jan 15, 2006)

Vinyl, not as durable as tile, but it flexes with the movement. I don't think moles move that much dirt. After the concrete pour, very often the dirt and fill settle leaving an air space. The only way to find this is to cut or drill the floor and look. 2 years ago, I built a house for the company I was working for. The front porch was filled with rock, tamped and sat for a month. 3 months later, the people were moved in and the porch cracked. We cut the floor section out and the rock was 1 1/4" below the bottom side of the concrete. No-one has explained where the rock went.


----------



## Dave Gobis (Mar 7, 2006)

Movement joints, expansion Joints or lack of control joints are the cause of this failure.

Why are movement joints needed? 

Recognizing that tile is a facade, movement joints are needed to eliminate stresses that can occur between the substrate and the tile due to differing amounts of expansion and contraction.

Where should movement joints be placed?

The Tile Council of North America's TCA Handbook recommends allowing for expansion and contraction in every tile installation. In small rooms, a gap at the perimeter of the room (often hidden by baseboard or shoe molding) is sufficient. For larger areas, the movement joints will be visible.

We can not specify the exact location nor frequency of movement joints as there many site related conditions that must be addressed - however, we do offer guidelines in Detail EJ171 in the TCA Handbook. It is especially important to note for interior installations, movement joints are placed more frequently when moisture or direct sunlight is expected. For exterior installations, the range of temperature from summer highs to winter lows must be considered.


Why do rooms with more sunlight need more movement joints? 
The intent of the guideline regarding sun exposure is to recognize that areas that get warm (or wet) may experience greater amounts of differential expansion. If the areas exposed to sunlight are warmer than surrounding areas, movement joints should be used more frequently. If the tile surface is not appreciably affected, no accommodation is needed in the joint spacing.

Only the area subjected to increased temperature needs to have movement joints more closely placed, not the entire floor if elsewhere the floor is an even temperature.


What other things should be considered when determining spacing for movement joints?

Many things can subject the tile layer to shear forces in addition to temperature and moisture. The following is a partial list:

· Continued curing of the concrete substrate can put the tile in compression
· Deflection and vibration of the substrate - particularly with suspended slabs
· Seismic activity
· Changes in the plane of the substrate
· Location of weight-bearing columns
· Type of tile or glass


From what is a movement joint made?

Movement joints are filled with material that allows for contraction and expansion. For floor applications, urethane, neoprene, or polysulfide are most often used in traffic areas and silicone sometimes where traffic is not a concern. Traffic areas require a sealant with a shore hardness of 35 or greater.



Tented Tile

What causes tile to tent?

Tile heaved off the floor, or tented, and sometimes cracked is often a sign that movement joints were not used sufficiently. For tile over concrete, the curing of the concrete places the tile under compression. 

Why do installations tent after a number of years?

How long it takes tile to tent is directly a function of at least three variables - the rate of concrete shrinkage, the shear strength of the thinset, and any expansive forces applied to the tile layer (heat for example). When the tile is poorly bonded, the tile can tent very quickly. If there is a strong bond, often the grout will compress significantly before the tile will lose its bond. Of course the type of tile is important as well - thinset has a harder time bonding to porcelain than most other tile. At the other extreme, I have seen a saltillo installation where the tile did not tent but rather spalled as the thinset and grout were stronger than the tile.

When tile fails with a loud report, this certainly indicates that a good bond was present. Only when the shear force exceeds the strength of the bond, will the tile let go. Frequently, either the tile or the concrete will be without thinset residue - as if the thinset was not applied correctly originally. Usually, if the tile is tenting years after the installation, this was not the case. Had the thinset not been applied correctly originally, the tile would have tented long before. Rather, it is important to consider that the cleavage plane will usually occur at the thinset transition - either the bond to the concrete or the bond to the tile, depending on the relative permeability and exact composition of each.

Hence, it is common to see one surface or the other sheared clean of thinset. Even in "explosive" failures where the tile cracks and "jumps" off the floor, usually one surface is free of thinset. Clearly a good bond had been established. 

With organic bonding agents and some of the polymer-modified thinsets, continued shear forces degrade the bond over time. So even when tile tents without an explosive report, the original installation may have had sufficient adhesive.

In summary, every installation should allow for movement. Properly designed installations, where expansion and contraction do not create shear forces, should have no problem for the tile to stay well adhered.


----------



## Jaz (Mar 21, 2006)

Hi Everyone,

I just saw this thread tonight and wish to say thanks to Dave for giving the correct answer.  

Mr. Gobis, as you know by now, is one of the most knowledgeable in our industry.  You should visit his website to find out what he does.

As for some of the other members that took a shoot at this question, (and other questions in this forum), please, if you are not qualified to answer any specific question, do everyone a favor and mention in your answer that you are not an expert in the particular field and it's just your layman's opinion.   This forum has many catagories and few of us are qualified to answer all of them.

Jaz


----------

