Tiles Popping Up

I learned this the hard way ….. in my own home. …..In our kitchen, we started having a rash of tiles coming loose off of our concrete slab foundation … so loose

that when you walked across the floor there was a “crunching” sound.  I pulled one and discovered that when the house was built the crew that stained and sealed the cabinets managed to also spray most of the floor.  Well …. water-based thin-set and oil-based stain/sealer don’t mix … which meant all the tiles near the cabinets had to be replaced.  When we went to remove the tiles, we found out that the previous owners tried to fix the same issue by just removing the tiles and re-applying an adhesive (of course, it was the wrong adhesive on top of all the other issues) — these tiles also came loose.

How did we fix the issue after removing all the tiles — in other words, how did we get the stain and sealer off of the floor before installing the new tiles?  Two approaches —

• Sand Floor — Rent a concrete floor finish sander that will remove a fine top layer concrete from the slab.  Be careful, this could be an extremely dusty process but some like this approach.
• Acid-etching — using a diluted (minimum of 5-t0-1) corrosive acid (Muriatic), along with protective clothing and eyeware (make sure you’re safe and everything around you), gently apply and brush-in with rubber brush on long handle.  This will remove both the top thin layer of the foundation along with the stain and sealant.

If you are uncomfortable with either of these approaches, please hire a contractor to work through the cleaning, and most likely, tile installation process.

PS — If you have a stained (purposely) concrete floor, a similar approach could be needed for tile installation preparation.  Of course, you could just go back with carpet.