Use a “1/8” - ”1/16” grout joint for optimal appearance and structural integrity. Install the tiles without offset to maintain the seamless look of the Urbanslat design. Please follow the installation recommendations for Urbanslat available on our website. Large format tiles: It is mandatory that the mortar coverage on the wall surface and tile be greater than 95% coverage to be fully supported. Voids due to insufficient coverage will result in cracking and tile displacement.