Tile Troubles Version 6
The TCA Team was created out of necessity as calls were consuming vast amounts of time for 4 or 5 people at TCNA and CTEF who had other jobs, answering calls about tile problems not being one of them. They provide a fulltime staff which can answer questions, consult, provide quality control and field inspections or if need be, forensic failure analysis. The pictures in this article are from a few of 100's of inspections they have performed in the past year. Unfortunately, the problems remain the same as always and even more unfortunately are still 97 to 98 percent installer error. I wish I could change that, but facts are facts. I will skip the editorial on why you should continually educate yourself regardless of how many years you have been in the business. Suffice it to say, if you are doing the same thing now that you were 30 years ago, you have a problem. Everything has changed but you.
This is a very large project that is having complete bond failure. Initial complaint was bad thinset. Possible? Sure. Likely? No. Most cement-based thinsets have a shelf life of a year, some only 6 months. Mr. I been doing it for 30 years would say no lumps in the bag, use it. An educated Mr. 30 Years would realize that some of the formulations in use today can go bad without a single lump anywhere, is just plain won't bond. The reason for this is highly technical and way beyond the scope of this article, but I am working on it. Regardless of thinset used if you have any curing compound, coatings such as paint overspray, dust and dirt, or any foreign substance on the substrate to which you chose to bond, you are at risk.
In the real world, finding a slab with no curing compound is very rare. Concrete industry standards recommend none be used if tile is to be applied. That raises the labor cost to the concrete contractor. Even if he were willing it could be challenging to locate a specific area where tile was to be installed on a 2,000 much less 20,000 s/f pour. The most reasonable alternative is to grind the areas to receive tile after the pour before the tile goes in. This is not a perfect world scenario, this is real world. If you feel like rolling the dice you could do water drop test. Place a few drops of water on the slab, if it absorbs immediately, your good to go. If it takes a few minutes to absorb either use a latex/polymer or if the tile required one, use a better grade. Ten minutes go by and the water is still beaded on the surface means it is time to leave and come back when the surface has been prepared. It will not bond if the water cannot be absorbed. It may be possible at this point to increase your income by preparing the slab. If you fix it for nothing, because you're a good guy and really want the job or account, be prepared to continue donating free labor whenever the problem occurs in the future.
Without question, the single largest caused of floor failures are caused by lack of movement accommodation joints. There is typically another reason associated with this failure, but not always. Tile grows when exposed to heat or moisture. When it is exposed to both it can really move. The industry recommendation for floors is a minimum of 1/4-inch movement accommodation at all wall perimeters and anyplace the tile abuts another rigid surface. There are many additional recommendations such as increasing joint size for temperature range in exterior environments and placing joints at changes of direction contained in both the TCA Handbook and under the American National Standards for the Installation of Ceramic Tile. One argument made fairly often, again by Mr. 30 Years is there is no way grouting against drywall will ever cause a floor to shear or "tent". Wrong again, it takes about 600# of uniform pressure to dent drywall.
So you're thinking well OK, maybe. "But I have a block wall with wire reinforced mortar and 1-by-1 porcelain mosaic. The wall is solid, reinforced, interior, low growth tile so I don't need no joints, it isn't going anywhere." Says Mr. 30 Years. Sorry, wrong again. The industry recommendation on walls is 1/8-inch movement at abutting surfaces and as determined appropriate in the field of installation by a qualified professional. All materials have a growth rate and they are all at different rates. While that may be one fine solid wall, it is still going to move.
A favorite term I heard from concrete guys in my contracting days was once it is cracked, it is cracked, the joint is dead and isn't going anywhere. In the real world, all you count on is it is going to move again. With rare exception, very rare, you will always find movement in a concrete separation or crack. Control joints are to control shrinkage and cause the cracks to occur in predetermined areas. There are concrete industry guidelines as to when and where they placement. A qualified person must make this determination, if your reading this article, your not it. All concrete needs control joints, there is no such thing as only in commercial construction, we don't do that on residential jobs. If there were no joints on a slab of any size it would be prudent to use a crack suppression membrane over the entire surface. If there are joints the tile must stop at that joint and a premade movement joint placed or appropriately constructed with caulk and a backer rod.
Grout Joints and Shading
Maybe we will finish this months article with another product that Mr. 30 Years says fails all the time, that brand X's is no good, never the right color, and gets effloresce due to poor quality of materials used in manufacturer, grout. Why pray tell does one of the most important part of the installation get left with low man on the totem pole? To find a decent grout job today is almost a rarity, it is very frustrating. We demonstrate various cleaning techniques weekly. It is actually much less work to do it right than wrong, a fact proven over and over again.
I have been working with several setting material manufacturers lately. You just can't truly appreciate how much these guys care about their products and performance. They are constantly helping out people who fail to follow instructions to the limits of their abilities. I spoke with one who recently had a slow month, 7,000 calls for product information and assistance. It keeps 4 people busy 8 hours a day, 5 days a week. Now is it really that complicated? Some of the questions just don't make any sense at all. Can you use brand Y primer for brand X self leveler or can I use brand Y self-leveler and brand X thinset. In theory possibly, in practice, do you really think brand Y tests brand X's product for compatibility with their own product? Not likely. If they do it is clearly stated in the instructions. Most tech calls are for reading instructions printed and readily available. As products evolve the instructions often change to reflect the new process. There are several things you can count on with tile work, something is always changing, everything is always moving, never enough time to put it in, always enough time to fix it. And to Mr. 30 Years and his buddy Mr. 20 Years (are they related?), I would really appreciate if you would read the instructions before you call, preferably before you do the job. Then we can talk about some of the finer points of the installation and what could have happened.