Tile tenting advice

[JeffersonX]

Hi,

I have reviewed several post and believe this is caused by the tiles not having expansion joints. In addition, the quarter round is caulked to the tile (done before we moved in, but until today I would not have thought that could cause a issue)

I have a home built in 2006 in Houston that has developed a problem in the last few days with the floor buckling. In the last week we had significant rain (over 5in on the 24th and nearly that much today, so close to 10 inches in 5 days or so).

We have never had issues with the floor lifting up or noticed hollow flooring in this area, although there are 4 to 6 tiles in the kitchen that sounded hollow when we moved in 4 years ago and some are cracked. Those tiles are 25ft from the new area. The new area is about two feet from an exterior wall. There is no signs of moisture intrusion from that wall or anywhere in the house. The wall that is close to the new area has a patio that has no problems with water drainage that I know of. The house was built in 2006 with a concrete slab foundation. I have no indication we have foundation issues. There are gutters all around the house. It is not in the flood plain. Although we did not live here during Harvey, the neighborhood had no flooded houses.

The tile is 24 x 24 ceramic tile. It is tenting about 2 foot from the wall. The floor sounds hollow for a few tiles in each direction, oddly a little more the further away from the wall, but not significantly so. None of the tiles appear to be cracked nor does the grout. As you can see by the pics, the lift is a lot. It surprises me the grout has not broken.

Any insight to what is happening and what we should do next would be greatly appreciated. In addition, what recommendations would you give me to discuss with a contractor to ensure it is diagnosed and repaired correctly.

My long term plan was to replace this tile with wood look ceramic tile. Since this is all rooms but the bedrooms of a 3,000 sq ft house, it will be a large expense. What are some other items to consider when doing the whole floor to avoid this issue. Thanks in advance for your help.

[jadnashua]

Tenting is almost always an issue with lack of movement accommodation...i.e., expansion joints. Texas has some issues with clay soils in more than a few places, and clay expands considerably when it gets soaked...10% volume change is not uncommon. That can mess with your slab, too.

If the quarter round is sitting on top of the tile, and not butted up to it, it isn't an issue as long as there's a gap to the wall. If the trim does sit tight to the tile, that's a problem.

Large expanses that have a lot of windows can be a big issue, too, as the solar can heat the tile before the slab, causing bonding issues as the tile expands versus the (slower to react) slab underneath.

Depending on how fast the movement occured, it doesn't always crack until the extent gets too great. It also depends on the type of grout...some are more flexible than others.

If you're going to remove the tile, you'll also want to check for cracks in the slab, and if there are any, check if their edge heights are even, or displaced vertically. If a vertical displacement, you should not put new tile down. If just horizontal, you'll need a crack isolation membrane to isolate that crack from the tile and 'honor' that crack with an expansion joint in the tile as well.

Cement grows a crystalline matrix when it cures. Those millions of small spikes are what hold things together. THey can shatter with movement, and the more that break, over time, can result in debonding once the bond degrades.

We've learned a bit more about how to tile things using modern products, so the recommendation for expansion joints is a bit more stringent than it was when your place was built.

[cx]

Welcome, Jeff.

If you don't add that geographic location to your User Profile, the information will be lost before we leave this page, and it's important in answering some types of questions.

Jim's got you pretty well covered there. I would suggest you remove the base quarter-round in a couple places to see if the tile was butted or grouted against the baseboard. If it is, that would likely explain the problem.

And if tenting is indeed the problem, the only solution I know of is to remove and replace the tiles, leaving an appropriate movement accommodation joint around the perimeter and where necessary in the tile field. Nobody wants to see such joints, but no one wants tiles removing themselves from the floor, either, eh?

My opinion; worth price charged.

[John Bridge]

Hi Jeff,

I spent quite a number of years installing tile on slabs in Houston and surrounds. I agree with all that has been said here. Although it varies, the expansion/contraction rate of a slab can be ten times that of ceramic tile. with no expansion joints something has to give.

[Redlands Okie]

If renting a box type straight edge is needed then keep in mind that concrete screet boards can be found at many rental centers in a variety of lengths. Unless they have been heavily abused they will be straight.