MAPEI has worked in concert with the International Masonry Institute of the International Union of Bricklayers and Allied Craftworkers (IMI/BAC) to produce Terratop, a unique new cementitious terrazzo. The IMI will train and certify installers in Terratop techniques, according to MAPEI. Terratop can be installed over existing concrete surfaces in a 3/8-inch layer. Any NTMA-approved aggregate or filler can be broadcast into the base, according to MAPEI.