# Calculation of Material Required For Brickwork

Calculation of Material Required For Brickwork

Today in this article we are going to learn how to calculate numbers of bricks in 1 Cum and how to calculate the quantity of cement and sand in brickwork.

Important Points For Estimation

Density of Cement                                     =  1440 kg/ m3

Density of Sand                                          =  1450 - 1500 kg/ m3

Density of Aggregate                                 =  1450 - 1550 kg/ m3

Quantity or Weight of Cement in 1 Bag    =   50 KG

The volume of 1 Bag Cement in Cum       =   0.03472 cubic meter

The volume of 1 Bag Cement in Cft          =   1.226 cubic feet

Numbers of Cement Bags in 1 cum           =    28.8 nos.

How many Cft in 1 Cum                            =   35.31 cft

How to calculate No. of bricks in 1 Cubic Metre?

Size of brick varies according to the region. In India, the standard size of the brick is = 9" x4" x3"

Size of one Brick in inches =  9" ×4" × 3"

Size of 1 Brick in Metre  = 9"×0.0254 × 4"×0.0254 × 3"×0.0254

= 0.2286 × 0.1016  × 0.0762
(1 inch = 0.0254 m)

The volume of 1 Brick      =  0.001769 cum

Numbers of brick in 1 Cum = 1/0.001769

= 565.29 say 565 nos

Brickwork Calculation

Take a wall

Length of wall = 20 metre

Width of wall   = 23 cm or 0.23 metre or 9"

Height of wall  = 5 m

The volume of wall = L × B × H

=  20 × 0.23 × 5

=  23 cum

Normally mortar joints are less than 1 cm ( 10 to 16 mm ). Let's consider it 10 mm or 0.39".

Add 0.39" in all face of brick excluding the front face.

Size of Brick = 9" ×4" × 3"

Add 0.39" in each face = (9"+0.9 × 4" +0.39 × 3"+0.39)

= 9.39" ×4.39" × 3.39"

The volume of Brick with Mortar = 9.39" ×4.39" × 3.39"
(1 inch = 0.0254 m)
= 0.002286 Cum

Number of Bricks in Wall = 23/0.002286

= 10061.24 say 10061 nos

Therefore, the number of bricks per cum of nominal size = Total nos of bricks in the wall/volume of wall
= 10061/23

=  437.43 say 437 nos. (approx)

Considering 5% breakages, wastages, etc., This may be taken 460 numbers per cubic metre.

Calculation of Quantity of mortar in Brickwork

Mortar Requirement = Total volume of brickwork minus net volume of bricks

=  23 - (9" × 4" × 3" × 10061)

=  23 - (0.2286 × 0.1016  × 0.0762 × 10061)

= 23 - 17.797       (1 inch = 0.0254 m)

= 5.2 cum

For frog filling, for use of cut brick, for bonding, for uniform joints, wastage, etc. 15% extra mortar may be required.

Therefore, the volume of mortar = 5.2 + 5.2 × 0.15

=  5.98 cum

For dry volume increase by 1/4

Dry volume of Mortar = 5.98 + 5.98 × 0.25

= 7.475 cum

For 23 cum of brickwork dry volume of mortar = 7.475 cum

For 1 cum dry volume of mortar = 7.475/23

= 0.325 cum or 11.47 cft

In practice, for cement mortar 3 cum dry mortar and for lime mortar 3.5 cum of dry mortar are taken for 10 cum brickwork. As an approximate 30% dry mortar may be taken.

Calculation of Cement and Sand in Mortar

Approximate method to determine the quantity of materials of mortar for 1cum brickwork divide 0.3 by the sum of the numerals of the proportion of materials which gives the quantity of cement in cum.

Example - For brickwork in 1: 6 cement mortar = 0.3/ (1+6) =
= 0.043 cum

Cement = 0.043 × 28.8 = 1.238 bags
Sand        =  0.043 × 6 = 0.258 cum

But as the cement will go to fill up the voids in the sand, 0.045 cum of cement and 0.27 cum of sand may be taken.