How to Calculate Bricks, Cement, and Sand in Mortar

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On July 6, 2025

Calculating the quantity of bricks, cement, and sand in mortar is a fundamental skill the construction industry. Whether you're estimating materials for a small wall or a large masonry project, understanding the precise calculation process helps avoid wastage, control costs, and ensure structural integrity. This article breaks down the essential steps and concepts for accurate material estimation in brick masonry.

What Is Mortar and Why Is It Important?

Mortar is a workable paste used to bind bricks or blocks together, fill gaps, and distribute loads evenly. It typically consists of cement, sand, and water mixed in specific ratios depending on the application. The quality and quantity of mortar directly affect the strength and durability of brickwork.

Key Inputs for Calculating Bricks, Cement, and Sand

Before diving into calculations, gather these essential parameters:

Parameter	Typical Value/Unit	Notes
Standard Brick Size	190 mm × 90 mm × 90 mm (0.19×0.09×0.09 m)	Modular bricks commonly used
Mortar Thickness	10 mm (0.01 m)	Thickness of mortar joints
Wall Thickness	Half Brick: 115 mm (0.115 m)	Full Brick: 230 mm (0.23 m)
Mortar Mix Ratio	1:6 (cement:sand)	Common for general brick masonry
Cement Density	1440 kg/m³	Used for converting volume to weight

Step 1: Calculate the Volume of Brickwork

The volume of brickwork is the product of the wall’s surface area and thickness:

\text{Volume of wall (m}^3) = \text{Area (m}^2) \times \text{Thickness (m)}

For example, a wall 3 m long, 2 m high, and 0.23 m thick has a volume:

3 \times 2 \times 0.23 = 1.38 \text{ m}^3

Step 2: Calculate the Volume of One Brick With Mortar

Including mortar thickness, the brick dimensions increase slightly:

Dimension	Without Mortar (m)	With Mortar (m)
Length	0.19	0.20
Width	0.09	0.10
Height	0.09	0.10

Volume of one brick with mortar:

0.20 \times 0.10 \times 0.10 = 0.002 \text{ m}^3

Step 3: Calculate Number of Bricks Required

Number of bricks per cubic meter of brickwork is:

\frac{1}{\text{Volume of one brick with mortar}} = \frac{1}{0.002} = 500 \text{ bricks/m}^3

For the example wall (1.38 m³):

500 \times 1.38 = 690 \text{ bricks}

Step 4: Calculate Volume of Bricks Without Mortar

The volume of one brick without mortar is:

0.19 \times 0.09 \times 0.09 = 0.001539 \text{ m}^3

Volume of bricks in the wall:

690 \times 0.001539 = 1.062 \text{ m}^3

Step 5: Calculate Volume of Mortar (Wet and Dry)

Mortar volume is the difference between total brickwork volume and brick volume:

\text{Wet mortar volume} = 1.38 - 1.062 = 0.318 \text{ m}^3

To account for drying shrinkage and wastage, multiply by 1.33:

\text{Dry mortar volume} = 0.318 \times 1.33 = 0.423 \text{ m}^3

Step 6: Calculate Cement and Sand Quantities in Mortar

Using the mortar mix ratio 1:6 (cement:sand), total parts = 7.

Material	Volume (m³) Calculation	Volume (m³)	Weight (kg) Calculation	Weight (kg)	Bags (50 kg each)
Cement	$\frac{1}{7} \times 0.423$	0.0604	$0.0604 \times 1440$	87.0	1.74
Sand	$\frac{6}{7} \times 0.423$	0.3626	N/A	N/A	N/A

Cement weight is calculated by multiplying volume by cement density (1440 kg/m³).
Sand quantity is typically measured by volume.

Table: Summary of Material Quantities for 1 Cubic Meter of Brickwork

Material	Quantity (Volume)	Quantity (Weight)	Notes
Bricks	500 bricks	N/A	Standard size bricks
Cement	0.0604 m³	87 kg	Approx. 1.74 bags (50 kg each)
Sand	0.3626 m³	N/A	Volume measurement
Mortar	0.423 m³ (dry)	N/A	Includes wastage

Why Accurate Calculation Matters

Cost Efficiency: Prevents over-ordering or under-ordering materials, saving money.
Structural Integrity: Ensures mortar strength is adequate for load-bearing.
Project Planning: Helps in scheduling and resource allocation.

Additional Tips for Students and Professionals

Always verify brick sizes as they may vary by region or manufacturer.
Consider different mortar ratios for specialized applications like reinforced masonry or wet environments.
Account for wastage during mixing and laying by adding 5-10% extra material.
Use dry volume calculations for precise cement and sand requirements, as wet volume underestimates material needs.

How to Adjust Calculations for Different Brick Sizes and Types

Bricks come in various sizes and types, influencing material requirements significantly.

Brick Type	Typical Size (mm)	Volume (m³) per Brick	Bricks per m³ of Wallwork
Standard Modular	190 × 90 × 90	0.001539	~650
Engineering Brick	215 × 102.5 × 65	0.001435	~700
Hollow Brick	400 × 200 × 200	0.016	~62

Note: Larger bricks reduce the number of bricks needed but may increase mortar volume due to larger joints or irregularities.

When using non-standard bricks:

Measure actual brick dimensions including mortar thickness.
Recalculate volume per brick with mortar.
Adjust number of bricks and mortar volume accordingly.

How to Calculate Mortar for Different Mix Ratios

Mortar mix ratios vary depending on structural requirements:

Mix Ratio (Cement:Sand)	Application	Strength (MPa) Approx.	Cement Volume (m³) per m³ Mortar	Sand Volume (m³) per m³ Mortar
1:3	Structural walls, high strength	12-15	0.25	0.75
1:4	General brickwork	7-10	0.20	0.80
1:6	Non-load bearing walls	3-5	0.14	0.86

Adjust cement and sand quantities based on the mix ratio chosen. For example, for 1 m³ of mortar at 1:4 ratio:

Cement volume = $$\frac1{1+4}$$= 0.20 m³
Sand volume = 0.80 m³

Accounting for Water and Additives in Mortar

Water is crucial for hydration and workability but is not typically included in quantity calculations because it evaporates. However:

Use clean water free from impurities.
Water-cement ratio is typically 0.4 to 0.6 by weight.
Additives like plasticizers or waterproofing agents may alter mortar volume slightly.

Common Mistakes in Calculating Bricks and Mortar

Ignoring mortar thickness: Leads to underestimating bricks required.
Not accounting for wastage: Always add 5-10% extra materials.
Using dry volume as wet volume: Mortar shrinks on drying; dry volume is larger.
Assuming uniform brick size: Variations require recalculations.
Overlooking joint thickness variation: Mortar joint thickness can vary on site.

How to Estimate Materials for Different Wall Thicknesses

Walls can be built with half-brick (115 mm), one-brick (230 mm), or multi-brick thicknesses.

Wall Type	Thickness (mm)	Bricks per m² (approx.)	Mortar Volume per m² (m³)
Half-brick wall	115	60	0.02
One-brick wall	230	120	0.04
One-and-a-half brick	345	180	0.06

Adjust calculations proportionally based on wall thickness and surface area.

Table: Material Quantities for Different Wall Thicknesses per 1 m² Wall Area

Wall Thickness	Bricks Required	Cement (kg)	Sand (m³)	Mortar Volume (m³)
115 mm	60	5.2	0.02	0.02
230 mm	120	10.4	0.04	0.04
345 mm	180	15.6	0.06	0.06

How to Calculate Cement Bags for Mortar

Cement bags typically weigh 50 kg. To calculate bags needed:

\text{Number of bags} = \frac{\text{Total cement weight (kg)}}{50}

For example, if you require 87 kg of cement, then:

\frac{87}{50} = 1.74 \text{ bags}

Always round up to the nearest whole bag to avoid shortages.

Practical Example: Estimating Materials for a 10 m² Wall (One-Brick Thick)

Parameter	Value
Wall Area	10 m²
Wall Thickness	0.23 m (one brick)
Volume of Wall	10 × 0.23 = 2.3 m³
Bricks Required	2.3 × 500 = 1150 bricks
Mortar Volume (dry)	2.3 × 0.318 = 0.731 m³
Cement Volume	0.731 × 1/7 = 0.104 m³
Cement Weight	0.104 × 1440 = 150 kg
Cement Bags	150 / 50 = 3 bags
Sand Volume	0.731 × 6/7 = 0.627 m³