QUESTION

How To remove Ceramic Tile Stains - I'm having trouble with ceramic tile floor on my rest room. There are few water log stains on the floor and I tried with many cleaning agents and brushes but no good, also tried pressure washer with 120 bar still no good. Can you suggest any method to renove water log stains on ceramic floor. See attached photo.

ANSWER

ANSWER - Unlike natural stone tiles, normally ceramic tiles are very resistant to moisture and staining, but it depends on the type of ceramic tile.

There are glazed tiles which has a glass like material on the surface that is impervious to moisture most of the time, but there are exceptions where moisture can migrate through a thin glaze. Glazed tiles normally don't stain.

Some glazed tile surfaces will darken when the body of the tile has been subjected to moisture. These glazed tile surfaces are normally more translucent than most glazed tiles. If you can dry the body of the stone out it will go back to the natural color unless the water that it was subjected to was dirty and leaves a residual after it dries.

Unglazed tiles (also referred to as through body tiles) are normally the most susceptible to staining because there is no surface coating and the material is the same throughout the tile. The porcelain or vitreous body tiles are impervious and very low absorbing, but there are other types of unglazed tiles that are very absorbing and susceptible to staining. Stains in these types of tiles can be removed the same way they are removed in natural stone with a poultice that draws the stain out of the tile.

Then there are stains that are caused by acidic materials that etch the surface of the tile that leave an indelible stain because the molecular structure of the tile has been altered.

After looking at the photo, it is hard to say what it is for sure without being there to inspect it, but my best guess is that the bathroom floor appears to have a moisture problem under the tile. Either there is a high water table in the ground or there is a pipe leaking somewhere keeping this area constantly damp.

The darkness looks to be the combination of dampness and probably there is some sort of microbial growth (mold) that has developed, which is not healthy.

If you have a electronic moisture meter you can verify there is high moisture under the tile by placing it on top of the tile.

You should remove the tile and clean and dry out the area if possible. Look for the source of the moisture and stop it if possible. If not possible to stop the moisture you can apply a special type of epoxy coating over the floor and then install the tile over it, as long as the moisture isn't the result of a hydrostatic condition.

A hydrostatic conditions is where there is water pressure pushing up on the bottom of the floor. If there is a hydrostatic problem due to high water table or water traveling to your building from somewhere else, then you have to build trench drains to redirect the water away from your building.

If the moisture is the result of high moisture vapor transmission there are some waterproof membranes that can be installed over the floor and then you can install the tile to it. Hope that helps. Good luck.