Ask the Building Maintenance Experts
Solutions for Your Toughest Problems

ICAN  Q & A  Home

Thursday, July 24, 2014

Question

I have a newly renovated terrazzo floor and within the last few months we have had big dark stains appear in the terrazzo. When we strip floor the stains are remaining.Has anyone had problems with these type stains and, if you have, can anything be done to remove them?


Answer

The terrazzo matrix has a porous cement in it and spills can seep down into the pores. At this point, no one likely remembers what was spilled or when, so this may be a challenge.
The next time you strip off the topical finish, make a poultice of an absorbent material such as baking soda and place it on the spot with the expectation that the soda, as it dries, will pull the oil or whatever up from the porous material and reduce the contrast with the surrounding surface. You may have to do this several times to see a difference, and keep in mind that the spill may have been sealed in by a penetrating seal, making it hard to reach.
Go on-line and search "terrazzo stains" for techniques to use on a variety of stains. You may have to experiment, perhaps using hydrogen peroxide with the baking soda to make a paste.

Lynn E. Krafft, ICAN/ATEX Editor
lekrafft@juno.com