Yes, build a floating seat up to 18“ in length on the walls. This can be made using a minimum 2“ thick wedi panel. Two of these panels can be glued to 4“ or thicker if needed. Use wedi joint sealant to bond the panel to the wall, but make sure the joint sealant is spread over the entire contact surface between wedi seat panel and wedi wall. You should use a fine tooth adhesive trowel with minimum 1/8” x 1/4” notches. All seams from seat to wall (on top of seat and below) shall be sealed over widely (1” either side of seam) using wedi joint sealant and a putty knife. Once this sealant has set, use wedi alkali resistant, and self- adhesive, mesh tape over the seams of top of seat to wall prior to tiling.
When building a seat from the floor up, it‘s best to apply standard framing practices. Install vertical support panels (2”) against walls, as sides to the seat, and for the front. wedi 2“ wedi building panel is also installed, within the seat construction, every 18“ for support. Include a sloped top (slope may be fabricated using wedi joint sealant wet shims or by cutting all supports accordingly) . After sealing and reinforcing the seams in the assembly, as well as seams between seat and wall with wedi joint sealant, you may have additional blue foam exposed. Simply key in thinset over these areas or install a wedi panel strip over these using wedi joint sealant. Cutting areas back to have them covered with a strip that is flush with the seat surface should considered when cutting and dry-fitting the seat assembly. A wedi building strip to cover exposed blue foam is definitely needed when the tile in this area will not overlap from the blue foam area onto the cement coated seat area (such as when working with mosaics). When building floor standing seats or benches in wert areas and over sloped surfaces, the front vertical seat panel will show a gap to the floor surface. This gap shall not be filled with sealant but should be backfilled with thinset mortar for strong support. wedi mesh tape is used in this thinset mortar application for reinforcement. When installing such seats or benches against areas which may be tiled already, or walls made of cement board or EPS panels, or which may, for any other reason(s) potentially allow water to enter the seat (e.g. from below wall tiles) it must be ensured it will not get stuck in the seat. The mesh and thinset cover over the front panel gap will allow water to exit. But if the floor was already tiled, and the use of thinset and mesh is not possible, it will be a good measure to drill a few relief holes into the bottom areas of the seat before tiling.