How Many Bricks per m² of Wall?
This calculator tells you exactly how many bricks you need to cover a given wall area in square meters. It works by dividing the net wall area by the face area of a single brick, then adding a standard waste factor. The core formula is: Bricks = (Wall Area m² ÷ Single Brick Face Area m²) × (1 + Waste Factor). Brick face area varies by type — a standard US common brick (3⅝″ × 2¼″ face) covers roughly 0.00527 m², while a modular brick covers about 0.00484 m². Use this tool when ordering materials for new construction, home additions, garden walls, or any masonry project where over-ordering wastes money and under-ordering causes costly delays.
When to use this calculator
- Estimating brick quantity and material cost for a new exterior house wall before submitting a contractor bid
- Planning a DIY backyard garden or retaining wall to buy the exact number of bricks at the hardware store without overspending
- Calculating leftover brick needs when patching or extending an existing wall to match the original course pattern
- Comparing material quantities for different brick types (common, modular, engineer, king-size) to choose the most cost-efficient option for a construction budget
Calculation Example
- Common brick, 20 m²
- 20 × 60 = 1,200 bricks
How it works
3 min readHow It's Calculated
The fundamental formula used by this calculator is:
Bricks needed = (Wall Area m²) ÷ (Brick Face Area m²) × Waste Multiplier
Where:
Brick Face Area (m²) = Brick Length (m) × Brick Height (m)
Waste Multiplier = 1.05 (5% waste, interior / simple pattern)
= 1.10 (10% waste, standard exterior)
= 1.15 (15% waste, diagonal / herringbone pattern)
Example – Common brick, 20 m² wall:
Face area = 0.2032 m × 0.0762 m = 0.015484 m² ← includes 3/8″ mortar joint
Bricks = 20 ÷ 0.015484 × 1.10 ≈ 1,421 bricks (with 10% waste)
Pure count (no waste): 20 ÷ 0.015484 ≈ 1,292 bricks> Note: The "face area" used in masonry always includes the mortar joint (typically 3/8″ = 9.5 mm) on the right side and top of each brick, because joints repeat across the whole wall.
---
Reference Table
Standard US brick sizes per ASTM C216 / Brick Industry Association (BIA) Technical Notes:
| Brick Type | Nominal Size (L × H × W) | Face Area incl. joint (m²) | Net bricks/m² | With 10% waste |
|---|---|---|---|---|
| Common / Standard | 8″ × 2¾″ × 3¾″ | 0.01548 | 64.6 | 71 |
| Modular | 7⅝″ × 2¼″ × 3⅝″ | 0.01113 | 89.8 | 99 |
| Engineer Modular | 7⅝″ × 2¾″ × 3⅝″ | 0.01355 | 73.8 | 81 |
| Closure Modular | 7⅝″ × 3⅝″ × 3⅝″ | 0.01790 | 55.9 | 61 |
| King Size | 9⅝″ × 2¾″ × 2¾″ | 0.01713 | 58.4 | 64 |
| Queen Size | 9⅝″ × 2¾″ × 2¾″ | 0.01713 | 58.4 | 64 |
| Jumbo Modular | 7⅝″ × 3⅝″ × 3⅝″ | 0.01790 | 55.9 | 61 |
| Norman | 11⅝″ × 2¼″ × 3⅝″ | 0.01697 | 58.9 | 65 |
| Roman | 11⅝″ × 1⅝″ × 3⅝″ | 0.01226 | 81.6 | 90 |
| Utility | 11⅝″ × 3⅝″ × 3⅝″ | 0.02731 | 36.6 | 40 |
All face areas include one 3/8″ (9.5 mm) mortar joint on the right and top edges.
---
Typical Cases
Case 1 — Standard Common Brick, 20 m² wall (no openings)
Case 2 — Modular Brick, 35 m² exterior wall with two 1.2 m × 1.5 m windows
Case 3 — Herringbone garden path wall, Norman brick, 8 m²
---
Common Errors
1. Forgetting to subtract door and window openings. Calculating gross wall area without deducting voids routinely causes 10–20% over-ordering on walls with multiple windows.
2. Using actual brick dimensions instead of nominal (mortar-inclusive) dimensions. A common brick is 7⅝″ long physically, but its nominal course dimension with a 3/8″ joint is 8″. Using the smaller number inflates your brick count significantly.
3. Applying a 5% waste factor for complex patterns. Diagonal, running bond on curved walls, or herringbone cuts generate 15–20% waste. The BIA recommends a minimum 15% waste allowance for non-standard bond patterns.
4. Ignoring the number of wythes (wall thickness). A single-wythe wall uses the figures above. A double-wythe (two bricks thick) wall doubles the brick count entirely — a very common oversight in load-bearing construction estimates.
5. Mixing metric and imperial inputs. If your plan dimensions are in feet and inches, convert fully to meters before entering into the formula — partial conversion (e.g., entering 10.5 when you meant 10′6″ = 3.2 m) leads to large errors.
---
Related Calculators
Since no related slugs were specified, explore other construction tools on Hacé Cuentas to complement your masonry estimate and plan your full project budget.
Frequently asked questions
How many bricks do I need per square meter for a standard wall?
For a US standard common brick (8″ × 2¾″ nominal face including mortar joint), you need approximately 64–65 bricks per m² of single-wythe wall. After adding the recommended 10% waste allowance for exterior walls, order 71 bricks per m². Modular bricks, being smaller, require about 90–99 bricks/m².
What waste factor should I add when buying bricks?
The Brick Industry Association (BIA) recommends: 5% waste for simple interior partitions with straight cuts; 10% waste for standard exterior walls in running or stacked bond; 15% waste for diagonal, herringbone, or curved-wall patterns. Never order zero waste — even experienced masons break bricks during cutting and handling.
Should I subtract windows and doors from the wall area before calculating?
Yes, always subtract the rough opening area of all windows and doors from the total wall area before calculating bricks. For example, a standard 3′ × 6′8″ door opening is about 1.86 m² — that's roughly 132 common bricks you would unnecessarily order if you skip this step. Some contractors keep a 50% credit on openings to account for extra cuts around the frame perimeter.
What is the difference between nominal and actual brick size?
Actual size is the physical dimension of the fired brick. Nominal size adds one standard mortar joint (3/8″ = 9.5 mm per ASTM C270) to each dimension. For a common brick, actual = 7⅝″ × 2¼″; nominal = 8″ × 2¾″. This calculator uses nominal dimensions because joints repeat uniformly across the entire wall surface, making the math accurate.
How do I calculate bricks for a double-wythe (two-brick-thick) wall?
Simply multiply the single-wythe brick count by 2. A double-wythe wall is used in load-bearing construction and historic restoration. For 20 m² of double-wythe common brick: 64.6 bricks/m² × 20 m² × 2 wythes = 2,584 bricks (net), or 2,842 bricks with 10% waste. Some double-wythe designs also include header courses that lock the wythes together, adding roughly 5% more bricks.
Does brick type affect mortar quantity as well?
Yes. Larger bricks (like Utility or King size) have fewer joints per m², so they require less mortar per square meter. A standard common brick wall (≈64 bricks/m²) needs roughly 0.018 m³ of mortar per m² of wall, while a Modular brick wall (≈90 bricks/m²) needs about 0.022 m³/m². Mortar mix ratios per ASTM C270 Type S (most common exterior use) are 1 part Portland cement : 0.5 part lime : 4.5 parts sand by volume.
Are US brick sizes the same as metric (European/Australian) bricks?
No. A standard metric brick (common in Australia, UK, and Europe) is 230 mm × 76 mm × 110 mm (actual), giving a nominal face of 240 mm × 86 mm = 0.02064 m² and approximately 48 bricks/m² — significantly fewer than US common brick at ~65/m². Always confirm which standard your supplier uses before entering dimensions, since mixing standards will produce incorrect estimates.
What ASTM standard governs facing brick quality in the US?
The primary standard is ASTM C216 (Standard Specification for Facing Brick), which classifies bricks by grade (SW = Severe Weathering, MW = Moderate Weathering, NW = No Weathering) and type (FBS, FBX, FBA). For exterior walls in freeze-thaw climates, Grade SW is required. ASTM C62 covers building (common) brick used in structural applications not exposed to view.