concrete from an outside source. If the tile is being set with adhesive or epoxy products, check with manufacturer for their limitation on moisture flow.” I have personally seen moisture mitigated by changes in guttering and landscaping by directing the water away from the slab. Regarding your final question, in my opinion it is an exact science for wood and resilient flooring but there is some gray area on the ceramic side, depending on the mortar, grout, tile and service envi- ronment. I hope this helps. – Robb Roderick, NTCA Trainer/Presenter Editor Note: There is a recent archived webinar called Concrete Moisture: The Good, the Bad, and the Ugly, available at http://www. tile-assn.com/?page=webinars. The webinar description: “It is common for concrete substrates to retain moisture. This rarely causes issues for ceramic tile installations, how- ever there are certain circumstanc- es where it can. This presentation explains how and why moisture is present in concrete slabs, shows how to evaluate concrete moisture levels and clarifies when and how to take precautions to ensure suc- cessful tile installations over moist concrete.” Just scroll down the list of archived webinars to listen to this – or any other – webinar, all presented by industry topic experts. ASK THE EXPERTS –––––––––––––––––––––––––––––––––––––––––––––––––––– High Quality Metal Trims and Pre-Molded Expansion Joints for all of Your Flooring Needs Call or click today! 800.236.5230 www.ceramictool.com Carpet/Vinyl Trim Reducers Reverse Trim Ceramic Tool MADE IN USA 24 TileLetter | September 2017