For the construction of walls above the plinth level, the suitable soil shall have a density of 2.5-3.5% by mass. For construction of walls below plinth level, the soil shall have a density of 5-7.5% by mass, so that the crushing strength of blocks made of soil-cement shall not be less than 1.4 N/mm2 for the dry condition. The unit weight of dry soil shall be considered as 1300 kg/m3 for calculation purposes.