# Calculation of Material Required For Brickwork

Calculation of Material Required For Brickwork

1. Calculation of Number of bricks required for 1 cum.

Take a wall 1and 1/2 brick with

Length of wall = 20 metre

Width of wall   = 30 cm or( 0.3 mtre)

Height of wall  = 5 m

The volume of wall = L × B × H

=  20 × 0.3 × 5

=  30 cum
Normally mortar joints are less than 1 cm, taking 1 cm mortar joints, the actual thickness of the wall be 29 cm.

Therefore actual volume = 20 × 0.29 × 5

= 29 cum

The volume of 1 brick of standard size 20cm×10cm ×10cm  = 0.20 × 0.10 × 0.10

= 0.002 cum

Now the number of bricks in wall  =  actual volume of wall/ volume of one brick

=  29/0.002

= 14500 Numbers

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

= 14500/30

= 484 numbers

Considering 5% breakages, wastages, etc., This may be taken 500 numbers per cubic metre.

Calculation of Quantity of mortar in Brickwork

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

=  29 - (0.19 × 0.09 × 0.09 × 14500)

= 29 - 22.315

= 6.685 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 = 6.685 + 6.685 × 0.15

=  7.688 cum

For dry volume increase by 1/4

Dry volume of Mortar = 7.688 + 7.688 × 0.25

= 9.61 cum

For 30 cum of brickwork dry volume of mortar = 9.61 cum

For 1 cum dry volume of mortar = 9.61/30

= 0.32 cum or 11.3 cft

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

Calculation of Materials of 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

Sand        =  0.43 × 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.