In construction work, the estimation of each work is done to know the exact volume of materials and the cost required. In this article, you will learn the method to calculate cost of concrete work.:D
Let we need to find out the cost of 1m³ concrete work of grade M15.
Here, the compacted volume of cement concrete = 1m³
Since, it is necessary to know that the dry volume i.e volume of cement, sand,
Dry Volume = 1x 1.55 = 1.55m³
Mix proportion of materials in concrete = 1:2:4 = 1+2+4 =7
Calculate volume of materials for the concrete
Quantity of cement required = 1.55 / 7 =0.221m³ =0.221 x 28.8 bags = 6.4 bags
Note: 1m³ cement =28.8 bags of cement
Quantity of sand required = 0.221 x 2 =0.442m³
Quantity of aggregate = 0.221 x 4 = 0.884m³
Let us assume,
the water cement ratio i.e w/c =0.5
Volume of water required =0.221 x 0.5 = 0.1105m³ = 0.1105 x 1000 liter = 110.5 L (1m³=1000 liter of water)
Skilled labour = 1.5 no.
Un-skilled labour = 7 no.
Calculate Cost of concrete Work
a) Cost Of Materials
- Cement = 6.4bags @ 800 per bag = Rs. 5120 ($51)
- Sand = 0.442m³ @ 2850 per m³ = Rs.1259.7 ($12)
- Aggregate = 0.884m³ @ 3500 per m³ = Rs. 3094 ($30)
- Water = 110.5 liter @ 1.5per liter = Rs. 165.75 ($2)
b) Cost Required for Labours
- Skilled Labour = 1.5 no. @ 750 per no. =Rs. 1125 ($11)
- Unskilled Labour = 7 no. @ 500 per no. = Rs 3500 ($35)
Sub-total = Rs 14264.45 ($142)
Add, 15% for contractor overhead and profit = 0.15 x 14264.45 = Rs 2139.64 ($21)
Total fund required for 1m³ cement concrete work = Rs 16404.12 ($164) Approximately.
In this way, we can find the total required amount for cement concrete work by rate analysis estimation process.