Tile & Stone Installation Systems Tiling over gypsum
When installing ceramic tile or stone over properly primed gypsum-based substrates, underlayments and patches, use any MAPEI tile mortars with a minimum ISO 13007 classification C2 or that meet ANSI A118.4. If an adhesive (mastic) is preferred, use one with ISO 13007 classification D1 or that meets ANSI
