Why are there white marks on my veneer stone? Can I remove them?
Q. Five years ago we built a home with a stone veneer front. We had water problems the first 4 years where water was leaking into several rooms and the basement coming from the front of the house. The stone was removed and replaced a couple of times (along with flooring in two of the rooms). We don't have as many water problems now, but we have noticed that several of the veneer stones have white marks on them. I noticed it a couple of months ago on only a couple of the stones, but now most of the stones have this white discoloration on them. It seems to be a hard substance that does not just brush off easily. The stones have also faded in color. We do have a southern exposure. Do you know what this white substance is that is taking over the surface appearance of the veneer stones? How do we get rid of this substance? Just one more....how do we stop the color from fading from our veneer stone? Thank you. I would appreciate any help or information you can give me. Janet Myer
A. As the moisture evaporates, it carries with it dissolved salts which are deposited on the surface of the stone. This condition, called efflorescence, is what you are seeing as a white powder. You most likely still have some sort of a water problem. Unless the water source is completely cut off it will keep coming back.
A color enhancing sealer may help bring out some of the faded color of the stone. However, because you have a preexisting efflorescence issue, it is possible that it may make the problem worse. I would recommend you do a test in a inconspicuous area with a color enhancing sealer to see if it provides you with some level of improvement to the color of the stone with out any negative effects.