- Determine desired location and trace around the outside of the Schluter®-KERDI-BOARD-SN flange, making sure the lines are level and plumb. Cut and remove the wallboard such that the niche will be supported on both sides by the studs or other wall framing.
- Insert the niche and fasten to the studs. When installing adjacent to KERDI-BOARD, use wood or metal screws and KERDI-BOARD-ZT washers, placing the fasteners along the seam between the KERDI-BOARD and the niche. When installing adjacent to gypsum board or other tile backers (e.g., CBU), use wood or metal screws only (i.e., no washers), placing fasteners approximately 1/4" (6 mm) from the edges of the niche. Fasten all corners and limit fastener spacing to 12" (305 mm) o.c.
- Connections between the niche and walls are made using KERDI-BAND or KERDI. When installed adjacent to KERDI-BOARD, seams are most easily constructed using KERDI-BAND. When installed adjacent to gypsum board or other tile backers (e.g., CBU), seams are most easily constructed by continuous application of the KERDI membrane. The membrane is applied up to the niche opening. Once the niche is sealed to the wall assembly, tile can be installed immediately using unmodified thin-set mortar.
- When using the prefabricated shelf, determine the desired height of the shelf and mark with a level line. Set tile using unmodified thin-set mortar up to that line on the back and sides of the niche. Butter the sides and back of the shelf with unmodified thin-set mortar and solidly embed it in the niche, resting on the previously installed tile. The shelf may be raised at the back to create a slope, or the tile may be set on a slope during installation, to prevent water from pooling in the finished application. Continue setting tile using unmodified thin-set mortar.