Inspired by colors, textures, and patterns decorative contractor Libby Donohoe precast interlocking concrete shapes to create the tile mosaic found in this bathroom. Trial and error led her to cast tiles in sheet molds--rubber sheets cut using a computer-controlled water-jet cutter. To cast the tiles, Donohoe backed the molds with plexiglass to act as a casting surface. The custom concrete mix included a superplasticizer, was integrally colored, and reached 3500 psi. Each square foot of the mosaic features 42 individual pieces. The tiles were soaked in water for seven days to cure then fit together into the pattern.
Donohoe polished the tiles to a 400-grit level, applied a densifier, then brought the entire mosaic to a 600-grit diamond finish using a handheld waterfed flex grinder/polisher. Although the floor tile was installed and polished onsite, the border tile was installed over cement board, polished, and then mounted to the wall. The bathroom took three months to cast and install the tiles.