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Pre-mounting mosaics methods (continued)

METHOD 3: FOAM OR CEMENTITIOUS BACKER BOARD Recommended when additional thickness is required for installation

Note: Before moving inlay, slide a piece of plywood or compa rable material underneath inlay using straps and/or appropri ate packing measures around all sides to stabilize inlay during transportation to jobsite

1. Cut foam or cementitious backer board to actual size of mosaic inlay (mosaic not to exceed size of backer board). 2. Place board onto a flat, horizontal surface, such as a worktable, and skim-coat board with thin set mortar (allow to cure per manufacturer in structions). 3. Sand down rough or high spots, trowel thinset mortar over backer board, then install mosaics. Clean perimeter of excess mortar. 4. Refer to ANSI Installation Specifi cations A108.14, A108.15, A108.16 for installation of mosaics onto back er board.

• It is recommended to produce a mock-up to ensure a prop er mortar bond • If glass tile is used, validate proper bond (ANSI A137.2) per manufacturer specifications • After installation, create soft joint at perimeter of mosa ic inlay as instructed by membrane manufacturer (ANSI A108.17) or, in the case of glass tile mosaics, refer to ANSI A108.16

5. Clean joints. Allow 48 hours for thinset mortar to cure before handling. Grout if desired.

NOTES: Transportation procedures for all tile mosaics will depend on size of panel. Sink savers, clamps, rolling carts with attach ment straps, and many other tools are available to stabilize the panel. In some cases, an A-Frame may be required. Pre-mounted mosaic tiles should not be used in submerged or exterior freeze/thaw applications unless recommended by manufacturers of products used.

6. After the inlay has fully cured, if needed, cover the face with a mosaic mounting tape for additional protection during trans portation and final installation of inlay.

NTCA Reference Manual | 2024 / 2025

Chapter 5 | Material Specific Products and Installation

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