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Wednesday, October 07, 2015


Some tile flooring has a gray discoloration on some of the tile in some small rooms. Stripping did not take it out. Do you have a remedy to remove this discoloration?


Two causes are most likely. First, if any of the wasted slurry (stripper plus dissolved floor finish) dries on the floor prior to removal, it will leave a gray residue. Remaining residue is often identified by the fact that it covers over the tile pattern. Standard mopping may not remove dried-on slurry. Instead, it requires re-dampening the floor and scrubbing with the machine or autoscrubber.
Second, it could be hardened sealer (normally permanent polyurethane or styrene based). Removing sealer may require up to three strip operations. Mix the stripper at the strongest use dilution, allow 15 minutes contact time, and use a build-up removal pad. Also, be prepared to razor blade scrape some of the most difficult areas.
Consult a previous ICAN - Ask the Expert post for tips on using a sanding disc. Keep in mind that a build-up removal pad or a sanding disc could void the floor covering warranty.
Gary Clipperton
National Pro Clean Corp.
(719) 598-5112