The water absorption is a parameter, which according to Brazilian standard specifications defines the class to which any clay-based product suits. In this work, we use a value of wa < 25% for bricks and wa < 18% for roofing tiles. As Shown in fig. 8, the brick’s specification was achieved in the studied temperature range (850-1150 C) for all ceramic pieces, while the specification for roofing tiles is attained only above 975 C.