HisabCalc › Country-specific

Brickwork Mortar Calculator

Find how many bricks a wall needs and the mortar volume, cement bags and sand for the chosen mix.

Enter your numbers

Wall area (sq ft)

Example: 100

Wall thickness (inches)

Example: 9

Cement to sand ratio

Wastage (%)

Example: 5

Result

Currency

Figures are computed on your device; nothing is sent anywhere.

Formula

wallVolumeIn3 = wallArea * (wallThickness / 12) * 1728; bricks = ceil(wallVolumeIn3 / ((9.5 + 0.4) * (2.75 + 0.4) * (4.5 + 0.4))); wetMortar = bricks * 35.244 / 1728; dryMortar = wetMortar * 1.33 * (1 + wastage / 100); cementBags = dryMortar * (cementPart / totalParts) / 1.226; sandVolume = dryMortar * (sandPart / totalParts)

How the calculation works

A brick with mortar joints takes more space than the brick alone, so the calculator counts bricks using a nominal size that already includes the joint.

The mortar volume is the gap left inside that nominal size, and it is increased by a dry volume factor and wastage because cement and sand are bought dry.

Common mistakes

Forgetting the mortar joint and dividing the wall volume by the plain brick size, which overstates the brick count and understates the mortar.

When to use it

Use it when ordering bricks, cement and sand for a wall before work starts, so materials arrive in the right quantities.

Worked example

For a 100 square foot wall 9 inches thick in a 1:6 mix with 5 percent wastage, you need 849 bricks, 17.32 cubic feet of mortar, 2.82 cement bags and 20.73 cubic feet of sand.

Bricks needed 849.00

Mortar volume (cu ft) 17.32

Cement bags 3

Sand volume (cu ft) 20.73

Common questions

Why is the mortar volume larger than the wall gaps look?

Because dry mortar loses volume when water is added, and the 1.33 factor plus wastage restores the amount you must actually buy.

Last updated: 2026-10-04