We have already discussed the importance of rate analysis. and how it will help us to face everyday scenarios.bricks calculation

Estimation of Material Quantity

Assume that we are going to analysis the rate for 1 Cum of  Brickwork (B.W) 

STEP 1 – Volume of single brick without mortar

Volume of 1 brick without mortar  = 0.19 x  0.09  x 0.09 = 0.0015 m3              

STEP 2 – Volume of single brick with mortar

While brickwork construction we will add cement mortar around 3 sides (left, right & top). 

So adding 10mm thick on each side of brick as mortar thickness 

The volume of brick with mortar = (0.19+0.010) x (0.09+0.010) x (0.09+0.010) =  0.20 x 0.1 x 0.1  = 0.002 m3 

Volume of 1 brick with mortar = 0.002 m3

STEP 3 – Number of bricks for 1 m3 Brickwork

Number of bricks with mortar for 1 m3 = 1 cubic meter / volume of bricks with mortar = (1/0.002)= 500 Nos

So the required number of bricks for 1 cum = 500 Nos

STEP 4 – Cement Mortar Volume for 1m3 of Brickwork

Cement Mortar Volume = Volume of brickwork with mortar – volume of bricks without mortar

Volume of bricks with mortar in 1 Cum = 500 x 0.002 = 1 m3

Volume of bricks without mortar in 1 Cum = 500 x 0.001539 = 0. 7695 m3

Therefore required cement mortar = 1 cum – 0.7695 cum = 0.2305 m3

Step 5 – Calculate Cement & Sand Volume

As we know the required cement mortar = 0.2305 m3

Assuming cement mortar ratio as 1:5 (1 Part Cement : 5 Part Sand)

We have already discussed the cement mortar volume calculation in plastering work post.

plastering calculation formula

The above formula will give a dry volume of cement mortar, So to get wet concrete volume, we have to multiply the dry volume by 1.33 

Total Parts = 1+5 =6

Required Volume of Cement = 1/6 x 1.33 x Mortar Volume = 1/6 x 1.33 x 0.2305= 0.0511 m3

To convert into cement bags  – (0.0511 x 1440)/50 = 1.47 Bags or 73.58 Kg 

Required Sand Volume = 5/6 x 1.33 x Mortar Volume = 5/6 x 1.33 x 0.2305 = 0.2554 m3

Required Material Quantity

Materials required for 1 m3 Brickwork is

  • 500 Numbers of bricks
  • 73.58 Kg or 1.47 Bags of cement
  • 0.2554 m3 of sand

Labour Estimation

From our thumb rule estimation (Labour Output Per Day), we are calculating the labour estimation as follow,

Description Unit Qty Rate Amount
Analysis of the rate for 1 Cum of  Brick Work (B.W) in Cement Mortar 1:5 (1 Cement: 5 coarse sand) using common burnt clay bricks of class designation 75, including curing, etc.
Materials
Cement Bags 1.47 350 514.5
Sand Cum 0.2554 1800 459.72
Bricks including wastage Nos 500 7 3500
Manpower
Mason Each 0.4 700 280
Male Mazdoor Each 0.5 500 250
Female Mazdoor Each 0.5 400 200
Waterman Each 0.2 400 80
Subtotal 5284
Tools & Tackles 1% 53
Add for Sundries & Contingencies 3% 158.5
Add for Over head & Contractor profit 10% 528
Total 6023.5
Rate per Cum 6023.5

You may download the Excel Sheet of Rate Analysis: Rate Analysis Sheet

Author

Satheesh is a Civil Engineer who has more than 9+ Years of experience in residential construction. He is the author, editor of Civil Planets

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