Estimation of materials is an important skill in construction.
First calculate the volume of mortar that is required:
Volume = Area * Thickness
= 100 m2 by 0.01
= 1 m3 `
This is the wet volume and it needs to be converted to dry volume for batching.
Ratio: 1.3 to convert from dry to wet volume.
Dry volume = 1.3 * 1 = 1.3 m3
For a strong mix, the mortar ratio of cement to sand is 1:3.
To get the volume of cement.
Cement :
Cement ratio /Total ratios= 1/4*1.3 = 0.325 m3
Taking the density of cement as : 1440 Kg/m3
Cement required: 1440 * 0.325 = 468 KGs
Cement bags(Assume 50KG bags) – 468/50 = 9.36 Bags
To get the volume of sand:
Sand ratio/Total ratio =3/4 *1.3 = 0.848 m3
Taking the density of sand as 1680 Kg/m3
Sand required = 1680 * 0.848 = 1424 KGs
Sand is sold in tonnes = 1424/1000 to give you the number of tonnes
Water content: 0.45 to cement volume
A good water ratio is 0.45/1
Therefore Cement volume: 0.325 m3
Water volume = 0.45 * 0.325 = 0.15 m3
Litres required are: 1000 * 0.15 = 150 Litres
For those building in Kenya, here are the common design mixes
Hoping this information has been useful. Build Wisely.
