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Mesh mounted mosaics in wet areas

not dissolve in water. If they are not water-soluble this can remedy the problem of falling apart when wet cutting. 2. Face mounting. By putting the adhesive mounting system on the face instead of the back, bond breaking layers and coverage are eliminated from consideration. This method may still be difficult to cut with a wet saw for the same reasons outlined above. a. Clear film face mounting allows for visibility and more control over placement, however ease of removal depends greatly on type of film and adhesive used. Often, removal of film must wait until the bond coat is set. b. Paper face mounting hides the mosaic initially but is easily removed shortly after initial set before the mortar has cured and allows for more adjustability during installation. Applicability of this method may be limited due to material limitations. 3. Non-water-soluble adhesives. There are various alternative adhesives available to manufacturers as options. UV cured adhesives, for example, are not water soluble and while more expensive, might be preferred over water soluble adhesives for horizontal wet or submerged applications. The effect on coverage is not a consideration, as the bond will be unaffected by the adhesive or by water exposure. CONCLUSION Mosaic tile will continue to be a fundamental part of the tile trade. It allows for beauty, unique design, and expression. That being the case, if we are to alleviate undue burden to installers in the field it is incumbent on the installer and the specifier/ design professional to verify with the mosaic manufacturer, the suitability of the mosaic in wet areas, but especially in horizontal wet areas like shower floors, steam rooms or in submerged applications like pools and fountains. While ANSI A137.1 does not contain a wet bond strength test, ANSI A137.2 and ANSI A137.3 do, and it could be requested of the mosaic manufacturer to run a bond strength test per the criteria in those standards to verify if the exposure to prolonged moisture has the potential to be a problem. Mesh mounted mosaics in non-submerged vertical applications have rarely been seen as problematic due solely to their mesh backing system coming loose or re-emulsifying after installation. Due diligence should be taken, especially with glass or stone mosaics, to verify with the manufacturer the applicability of their products in a desired application, either through testing or documented clarification of applicability. For glass mosaics, request ANSI A137.2 testing which should validate that proper bond can be achieved to the specific finish. It is incumbent upon the installer to verify the proper bond to a mosaic sheet, perhaps by producing a small mockup.

Photo courtesy of NTCA Members Unique Mosaics LLC and Elite-Tile Co.

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Chapter 5 | Material Specific Products and Installation