The invention discloses a 
building construction method for a wall. The 
building construction method comprises the following steps that (1) wall building is conducted, specifically, steel bars are erected in the positions, corresponding to the indoor wall, of a construction site, and a 
brick wall is built through piling outside the steel bars; (2) a wall blank is formed, specifically, concrete is poured in the 
brick wall and the steel bars, and the wall blank is formed after the concrete is solidified; and (3) plastering is conducted, specifically, plastering operation is conducted on the wallthrough 
mortar, wherein the preparation method of the 
mortar comprises the following steps that after building waste is crushed by a crushing device, 
crushed stone is obtained, then the crushed stoneis made into sand through a sand-making 
machine and thus the sand is obtained, the sand, 
cement and water are mixed and stirred, and thus the 
mortar is prepared. The sand and stone are manufactured directly by the building waste, so that waste of the non-renewable resources is avoided effectively; besides, 
pollution of the building waste to the 
ecological environment can be also avoided directly,and protection of the 
ecological environment is improved further; and various investments in treatment of the building waste are saved, the 
engineering cost is reduced effectively, and meanwhile the municipal expenditure can be also reduced to a great extent.