My house is built on crawl space (1962) then a slab composed of red brick slabs then 3 / 4cm of sand, a screed of 2 / 3m then the tiling which crack. Should I remove the screed and sand (some say it's used as insulation) or should I tile over the old tile? If yes it could pose a problem of weight because I am told that on this kind of construction must not exceed a certain weight per m2 on the other hand if the cleft crack is that the sand forms mounds next the passage and the screed above eventually break. What solutions should I do?
Two solutions are available to you or you drop the old tiling and redone the tile floor in its entirety (this would be the best solution); either (simpler solution), you opt for the creation of a dry screed over your old tiling. Light, it allows to renovate soil very damaged because this technique makes it possible to make up for irregularities.
You can then cover it with the coating of your choice. Refer to our fact sheet: DRY CAP AND FLOOR PANELS. Attention: after this operation you will plan the bottom of your doors (calibration).
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