“…In lightweight concrete, the fine aggregate can be replaced by ash. Taking into account the possibility of replacing already known wall materials by materials with ash and slag waste [14] in multilayer enclosing structures as a constructive material, it is possible to reduce the amount of capital costs for the construction of outdoor structures. The use of the ash and slag waste helps to save on materials -aggregates and fillers, and in addition when using ash and slag waste, it is possible to resolve the issue of waste disposal, which lie in the dumps, and at the same time damages the environment [15,16].…”