How to remove moisture from a Calacatta marble floor?
Estimated Reading Time: 2 MinutesQ. I am facing a problem with my Calacatta marble floor. Some tiles are getting darker because of the moisture content increment, so is there any chemical that can be used to suck out the moisture from marble, and return it into white color? Thanks in advance.
A. When Calacatta marble absorbs water, it naturally gets darker, just as you describe. Unfortunately, there is no chemical that can pull the moisture out.
If the floor was installed recently, the darkening can simply be leftover moisture in the setting materials or substrate that needs more time to evaporate. Hopefully, that's the case.
The moisture may be caused by a plumbing leak, a damp concrete slab, or missing waterproofing in certain areas. If the dark tiles are concentrated around the edges of the room, that usually means moisture is coming from the walls or a nearby pipe. If the dark spots appear randomly across the floor, it often points to moisture trapped in the mortar bed or a slab with uneven moisture levels. If the darkening shows up mainly in areas where water is commonly used, like in front of a shower or near a sink, it may be surface water getting through unsealed grout joints or small gaps in the stone. The real solution is to figure out the source of the moisture and eliminate it.
The marble will slowly dry out and return to its normal color with the moisture problem resolved. You can set up a dehumidifier and run an air conditioner (which also works as a dehumidifier). Depending on how deep the moisture is, the drying time can be quite lengthy. It could take weeks or even months.
If any marks remain after the floor has fully dried, a stone restoration professional can remove mineral deposits or refinish the surface if needed. To find a vetted PRO in your area, visit www.surfacecarepros.com and click on Find a PRO.
It is possible, in certain scenarios, that the entire floor will need to be removed and new marble tiles installed. Be sure to get advise from your PRO or a stone inspector before making any costly decisions.
ABOUT THE AUTHOR Fred Hueston is the Chief Technical Director at SurfaceCarePROS.com and Director at StoneForensics.com. He is also the author of Stone and Tile Restoration: The Manual, a comprehensive online manual for stone and tile restoration contractors. [Learn more about Fred.]