TryBuildCalcBrick Calculator With Mortar(Brick Quantity, Mortar Joint & Wastage)
Calculate bricks with mortar joint thickness.
Use this brick calculator with mortar to estimate brick quantity while considering mortar joint thickness, wall dimensions, wall thickness, and construction wastage.
🕒 Last updated: August 21, 2026
Inputs
💡Enter custom brick dimensions (excluding mortar).
Cost
Theoretical Bricks
465
Wall Area: 9.29 m²
Wall Volume: 0.836 m³
Bricks per m³: 556 bricks/m³
Bricks per m²: 50.1 bricks/m²
Derived Thickness: 90 mm
Recommended Bricks (5% wastage)
489
Wastage Quantity: 24 bricks
Recommended Density (per m²): 52.6 bricks/m²
Recommended Density (per m³): 585 bricks/m³
Includes wastage allowance for cutting, breakage and site handling.
Why mortar thickness matters in brick calculation
Mortar joints increase the effective module size of each brick. That means the same wall volume can require a different number of bricks when joint thickness changes.
For standard brick presets, this calculator uses practical empirical values. For custom brick sizes, it uses the entered brick dimensions and mortar joint thickness.
- Typical mortar joint thickness is around 10 mm.
- Thicker joints reduce the calculated brick count but may increase mortar use.
- Use custom brick size when you want mortar thickness to directly affect the brick count.
How does this brick calculator work?
Understanding how brick quantity is calculated helps in verifying estimates and planning construction materials more effectively.
Brick quantity is determined using empirical masonry density for standard bricks and modular volume calculations for custom bricks.
Step 1 — Wall Volume
Wall volume is calculated as:
Where:
- Length — wall length
- Height — wall height
- Thickness — wall thickness (derived from brick size or selected bond)
Step 2 — Brick Masonry Module Volume
For custom bricks:
Effective Brick Length = Brick Length + Mortar Thickness
Effective Brick Height = Brick Height + Mortar Thickness
Effective Brick Width = Brick Width
Then:
Step 3 — Bricks per Cubic Meter
This represents the number of bricks required to construct 1 cubic meter of masonry. For standard bricks, empirical values are used based on industry practice.
Step 4 — Total Brick Requirement
Then wastage allowance is added on top of the rounded theoretical count:
Wastage Bricks = round up(Theoretical Bricks × Wastage %)
Adjusted (Recommended) Bricks = Theoretical Bricks + Wastage Bricks
Both the theoretical count and the wastage allowance are rounded up separately to whole bricks, since bricks can only be purchased as whole units. Because of this two-step rounding, the final recommended quantity can differ by a few bricks from simply multiplying the unrounded total by (1 + Wastage %).
Real-World Brick Calculation Example
This example uses the active calculator inputs and explains the complete calculation method step by step. Each table shows the formula, values placed into the formula, and the final result.
Input Values Used
| Input | Value | Purpose |
|---|---|---|
| Wall Length | 10 ft | Site wall length |
| Wall Height | 10 ft | Site wall height |
| Wall Thickness | 90 mm (custom) | Derived from custom brick width |
| Brick Type | Custom (190 x 90 x 90 mm) | Determines module volume |
| Mortar Joint Thickness | 10 mm | Added to brick length and height for the module volume |
| Wastage Allowance | 5% | Added on top of the theoretical brick count |
Step 1 — Calculate Wall Volume
| Calculation | Formula / Substitution | Result |
|---|---|---|
| Wall area | 10 ft × 10 ft | 9.29 m² |
| Wall volume | 9.29 m² × 0.0900 m | 0.836 m³ |
Step 2 — Determine Bricks per Cubic Metre (Modular Method)
| Calculation | Formula / Substitution | Result |
|---|---|---|
| Effective brick length | 190 + 10 mm | 200 mm |
| Effective brick height | 90 + 10 mm | 100 mm |
| Brick module volume | Effective L × Effective H × Width, converted to m³ | 0.001800 m³ |
| Bricks per m³ | 1 ÷ 0.001800 m³ | 555.6 bricks/m³ |
Step 3 — Calculate Theoretical Bricks
| Theoretical bricks | round up(0.836 m³ × 555.6 bricks/m³) | 465 bricks |
Step 4 — Add Wastage Allowance
| Wastage bricks | round up(465 × 5%) | 24 bricks |
| Recommended bricks | 465 + 24 | 489 bricks |
Therefore, for this input, you need approximately 465 bricks (theoretical), or 489 bricks including a 5% wastage allowance — approximately 50.1 bricks/m² of wall face.
Practical Ordering Note
Standard brick types use an empirical bricks-per-m³ value already validated by industry practice. Custom brick types are instead calculated from the exact module geometry, which is why the same wall can give a different count when you switch from a standard brick to a custom one with similar dimensions. This estimate also does not deduct door and window openings — subtract their area separately for a tighter order quantity.
Limitations of brick estimation
This calculator provides an estimate based on standard brick sizes and rectangular wall geometry. It does not account for openings such as doors and windows, complex wall shapes, or decorative brickwork patterns. Actual brick requirements may vary depending on site conditions.
Unlike basic brick calculators that rely only on area-based estimation, this tool uses both empirical masonry density and modular volume calculations to provide more realistic and flexible results.
This calculator is based on standard masonry estimation practices used in civil engineering and quantity surveying.
Related Calculators
Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.