The ‘screed’ or ‘re-screed’ sand is a material specially formulated for on-site production of pumpable semi-dry mortars, to which only cement and a small amount of water need to be added. It is mechanically mixed and pumped with compressed air to the application site. Forming a 5 to 8 cm layer, this mortar prepares the base for the subsequent laying of sandstone, parquet, etc.