*
I layed ceramic tile in my basement. The floor is concrete. I have in-floor hydronic heat in the basement. Now, many of the tiles have a hollow sound and are easily dislodged.
Before laying the tile, I swepted and mopped the floor, but did nothing else to it.
What did I do wrong and how can I prevent it. Does the hydronic heat have anything with the tiles coming lose? Did I just fail to prepare the floor properly?
Don Coe
Replies
*
Don,
My guess would be that someone applied concrete curing and sealing compound to your concrete floor just after it was poured. Nothing, including thinset, sticks to this stuff. I have found that the only dependable way to tile over it is to sand it with very coarse sanding material until you get into the raw concrete. A second possibility is that someone poured the floor when it was freezing cold and the surface will powder forever, allowing your adhesive to pull away. These are the two most common problems that I have found. If this is not your problem, then perhaps it was contaminated on the surface with something else. A good wash with a commercial masonry cleaner will usually remove anything else. Sounds like a nasty problem. Make sure that you use a quality, latex modified adhesive, and that you really press it onto the floor with the flat part of your trowel before you use the notched side. Hope this works out for you!.........
*I agree with G. LaLonde that this may be your problem. However, if this is the problem, I'd want a mechanical bond. You can bushhammer the slab to prepare for tile.Another source of loose tiles may be excessive hydrostatic pressure. Basically, this is water pushing up from underneath the slab. Does your slab "sweat"?To check, place something dry, non absorbant directly on the exposed slab. Leave it in place for a day, a coupla' days, a week. Check for moisture at each of these intervals.If moisture has formed under this you may have this problem.
*
I might recommend another solution and diagnosis in addition to the other fine ideas set forth above.
Prior to laying you tile, I would take a real stiff metal brush or a 5" grinder with a brush on it, and scuff up the surfacw of the concrete.
I would also perform an acid wash on the concrete, purchaisng the acid from your local tile dealer. There are several products out there, and I would stay clear of muriatic acid, unless you are very familiar with it, significantly dilute it, and wear very protective clothing. Your tile dealer should have something a bit tamer.
Good Luck!!
*I've only been monitoring this site for a couple of weeks, but the advice you have received is the best I have seen. The best fix may depend on the square footage of the area you are tiling. Bush hammering is the best way to increase the bond, but it is slow and hard on the operator. I recently tiled a museum floor that was about 1200 sf. I used a mechanical scarifier to roughen the slab. There was no curing compound, but the slab was steel trowelled until it was slick as ice. I would have used a shot blaster, but could not find one at my local rental shops. Good luck with your floor.
*
I layed ceramic tile in my basement. The floor is concrete. I have in-floor hydronic heat in the basement. Now, many of the tiles have a hollow sound and are easily dislodged.
Before laying the tile, I swepted and mopped the floor, but did nothing else to it.
What did I do wrong and how can I prevent it. Does the hydronic heat have anything with the tiles coming lose? Did I just fail to prepare the floor properly?
Don Coe
Hi Don,
It's possible that you didn't prepare the concrete floor properly before laying the tiles, which could be causing the hollow sound and loose tiles. It's important to make sure that the floor is clean, level, and free of any debris before laying tiles. The hydronic heat may also be contributing to the issue, as temperature changes can cause materials to expand and contract, potentially affecting the tiles. You may want to consult with a professional to assess the situation and provide advice on how to prevent further issues. Good luck!