When setting tiles on a Fundo Primo or Riolito shower base that are equal or smaller than 1“square, use an epoxy thinset as these tiles sometimes rock over trowel lines, and use epoxy grout to better connect the small tiles at their edges. Tiles smaller than 2” x 2” square, but larger than 1” x 1” square may be set in modified thinset (ANSI 118.4 class) but must be grouted with epoxy. Pebble Stones may be set in epoxy or modified thinset and should be grouted with a sanded cementitious grout. Over Fundo Ligno, tiles smaller than 2” x 2” square or pebble stone must not be used.
Over all wedi Fundo shower bases , tile sizes larger than 2” x 2” are not limited and all large format tile may be used, provided that grout lines are fabricated where wedi bases show their slope lines between different and adjacent slope fields.
Please note, many tile formats or patterns mix smaller and larger tiles. In addition , many types of tile have no square format or sizes and feature longer and shorter sides. Always use the shortest side of a tile, or the smallest tile in the assembly to determine the proper choice of setting materials including grout.
When installing river rock or pebble stones, skim coat the pan using modified thinset or epoxy thinset, then begin setting your stone, and use grout recommended for this application by the grout manufacturer. *When installing river rock mounted on mesh, be sure the thinset below the river rock bonds fully to the rock. In some cases you may want to remove the mesh. Ensuring maximum adhesion when using any mesh mounted tile is a challenge. When in doubt, remove the mesh.