Before going for the calculation process to find out the mortar quantity for brick wall. We must have to follow these steps carefully for the mixing process of mortar.
How to mix cement mortar?
- The mix should be by volume.
- The quantity of water should be such that the mix can be easily spread over bricks or
applied on a vertical surface.
- The mix should be as per the specifications.
- Mortar should be used within half an hour of its preparation.
Now, lets come to the calculation process.
We assume that the required mortar for the construction of 1 m³ and the class of brick is first class and brickwork using the ration of 1:4 cement, sand mortar.
Calculation Procedure for finding mortar required for brick wall
Brick Size: An standard size of 230mm x 110mm x 55mm
Mortar Thickness: Assume 10mm thickness of mortar and add on standard dimensions of the brick i.e size of a brick with 10 mm mortar joint-240mmx120mmx65mm.
Estimate Brickwork (V): Let’s assume V=1 m³
To Calculate the Number of Bricks:
Number of bricks for 1m³ brickwork
= Total brickwork volume / Volume of brick with mortar
= 535 no.
To Calculate the Total Volume of Brick = Actual size of brick x Number of brick
= 230mm x 120mm x 55mm x 535
Now, Wet Volume of Mortar = Total volume – the total volume of a brick
= 1-0.081=0.187 m³
Usually, dry volume is 40-53% more than the wet volume so to calculate
Dry Volume of Mortar = wet volume of mortar x 1.5
= 1.5 x 0.187
= 0.2805 m³
We can also find out the volume of sand and the number of cement bags used in the 1 m³ brickwork.
As we already mentioned above we take the 1:4 cement-sand ratio in mortar.
First add the ratio i.e 1+4 = 5
Now, divide by the added ration and multiply that ration with the portion.
Volume of cement = (total dry volume of mortar / 5) x portion of cement in cement-sand mortar
= 0.0561 m³
= 1.65 bags
For the volume of the sand = (total dry volume of mortar /5) x 4
=(0.2805/5) x 4 = 0.2244 m³
In this way, we can estimate the required mortar including the number of cement bags required and the volume of sand required for the specified mortar respectively.