Tuesday's Ask the Experts: Sealer versus finish
Sealing of cement based grout lines (not glazed tiles) with a penetrating or impregnating sealer is recommended to prevent the penetration of urine, moisture and soil into the porous material and subsequent bacterial growth, odor and discoloration. This assumes a good, non-slip ceramic tile is in place, as is most appropriate for rest rooms and ease of cleaning. If you are faced with resilient tile restroom floors... — Lynn E. Krafft, ICAN/ATEX editor
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