Tile removal: remove or level thinset before floating floor installation?
I’m currently removing the damaged tile floor in my kitchen and foyer with the intention of installing floating laminate, engineered wood, or LVP planks.
The tiles are 12×24 unglazed porcelain. Original thinset was a Mapei or Versabond product.
We noticed that the flooring in the kitchen was “crunchy” shortly after installation about 10 years ago, with grout cracks and loose tiles appearing increasingly since original installation. The flooring in the foyer has remained intact without issue from the beginning. The original tile installer used a wire mesh and sand-mix mud bed over my 2×6 diagonal plank subfloor. No plwyood or OSB subfloor reinforcement was installed. I did notice that each tile was backbuttered and firmly set into the thinset during installation. I’m not sure if the lack of subfloor reinforcement, improper thinset installation, or something else entirely contributed to the floor failure.
The tiles come out easily now and I’ve noticed that there is little to no thinset adhered to the back of each tile. The thinset on the floor appears to be decent shape and has been pressed by the tile installation to form a generally flat plane with some shallow 1/2″ wide grooves left by the trowel and even shallower 1/8″ grooves left by the underside of the tile itself.
Here are my questions:
1. Given that the tile removal is revealing a generally flat plane left by the thinset with only shallow grooves, can I install underlayment over top this followed by floating click-type flooring?
2. Or will I have to remove the thinset prior to the installation of another flooring?
3. Can I fill-in the shallow thinset grooves with a skim-coat of new thinset, concrete resurfacer, levelling compound, or even a runny-sand mix? Will any of these adhere properly to old thinset?
Any thoughts from some pros would be appreciated.