# Brick Calculator

> Counts the bricks in a single-leaf (half-brick, stretcher-bond) wall from its length and height using a standard brick size with its mortar joint, adds waste, and estimates the mortar volume geometrically and the bags of mortar mix from a manufacturer rule of thumb.

- Calculator id: `brick` · Category: Construction & Home (`construction`) · Tool name: `estimate_bricks_needed`
- Canonical page: https://tttkmbb.com/construction/brick · This document: https://tttkmbb.com/construction/brick.md · JSON definition: https://tttkmbb.com/construction/brick.json

## Purpose

Counts the bricks in a single-leaf (half-brick, stretcher-bond) wall from its length and height using a standard brick size with its mortar joint, adds waste, and estimates the mortar volume geometrically and the bags of mortar mix from a manufacturer rule of thumb.

**Use when:** You need the number of bricks and the mortar for a garden wall, veneer or single-skin wall of known face area.

**Do not use when:** The wall is concrete block (use the block face 440 × 215 mm or 8 × 16 in as a custom brick) or two leaves thick: double the brick count, or use concrete-slab for footings.

## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `unit_system` | enum: metric \| imperial |  | optional, default "metric" | Unit system of the length inputs (metric: m / cm / mm; imperial: ft / in). Outputs are reported in both systems. |
| `wall_length` | number | m or ft | required | Length of the wall face (m or ft). (> 0, max 10000) |
| `wall_height` | number | m or ft | required | Height of the wall face (m or ft). (> 0, max 100) |
| `brick_size` | enum: us_modular \| uk_standard \| au_standard \| de_nf \| metric_modular \| custom |  | optional | Brick format. Default uk_standard (metric) or us_modular (imperial). |
| `brick_length` | number | mm or in | optional | Brick length for brick_size = custom (mm or in). (> 0, max 1000) |
| `brick_height` | number | mm or in | optional | Brick height for custom (mm or in). (> 0, max 1000) |
| `brick_width` | number | mm or in | optional | Brick width (wall thickness) for custom, used for the mortar volume (mm or in). (> 0, max 1000) |
| `mortar_joint` | number | mm or in | optional | Joint thickness for custom bricks. Default 10 mm (metric) or 3/8 in (imperial). (min 0, max 50) |
| `waste_percent` | number | % | optional, default 5 | Extra material for cuts, breakage and offcuts, applied as a multiplier (1 + waste_percent/100). 5 % covers cut and broken bricks on plain walls; 10 % for walls with many openings or corners. (min 0, max 50) |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `wall_area_m2` | number | m² | wall_length × wall_height. |
| `wall_area_ft2` | number | ft² | Wall face area in square feet. |
| `bricks_per_m2` | number |  | 1 / ((length + joint) × (height + joint)). |
| `bricks_per_ft2` | number |  | Bricks per square foot. |
| `bricks_needed_no_waste` | integer |  | ceil(area × bricks_per_m²). |
| `bricks_needed` | integer |  | ceil(area × bricks_per_m² × (1 + waste_percent/100)). |
| `mortar_volume_m3` | number | m³ | Geometric joint volume: area × brick_width − bricks × brick volume. |
| `mortar_volume_cubic_feet` | number | ft³ | Same volume in cubic feet. |
| `mortar_bags_80lb` | integer |  | ceil(bricks_no_waste / 37): QUIKRETE states one 80 lb (36 kg) bag lays up to 37 standard bricks, waste included. |
| `mortar_bags_25kg` | integer |  | ceil(bricks_no_waste / 25), the 80 lb figure pro-rated by bag mass. |

## Formula

`bricks_per_m² = 1 / ((L + j) × (H + j)); bricks = ceil(wall_area × bricks_per_m² × (1 + waste/100)); mortar_m³ = wall_area × W − wall_area × bricks_per_m² × L × W × H; bags_80lb = ceil(bricks / 37); bags_25kg = ceil(bricks / 25). US modular uses the nominal 8 × 2⅔ in course module (3 courses = 8 in).`

Single-leaf stretcher bond only; the geometric mortar volume (≈ 0.018 m³ per m² for UK bricks, close to BIA's 5.5 ft³ per 100 ft² for modular brick) excludes frogs, perforations and dropped mortar, which is why bag counts use the manufacturer's per-brick rule instead.

## Data Sources

- Brick Industry Association – Technical Note 10: Dimensioning and Estimating Brick Masonry — https://www.gobrick.com/media/file/10-dimensioning-and-estimating-brick-masonry.pdf (standard, retrieved 2026-09-23)
- QUIKRETE Mortar Mix No. 1102 product data sheet (80 lb bag lays up to 37 standard bricks) — https://www.quikrete.com/pdfs/data_sheet-mortar%20mix%201102.pdf (reference, retrieved 2026-09-23)
- Wikipedia – Brick (standard sizes by country) — https://en.wikipedia.org/wiki/Brick (reference, retrieved 2026-09-23)

Data freshness: `static`. Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output.

## API

- `GET https://tttkmbb.com/api/v1/calculate/brick?wall_length=…&wall_height=…`
- `POST https://tttkmbb.com/api/v1/calculate/brick` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/brick · OpenAPI operationId `estimate_bricks_needed` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool:  `run_calculator` with `{"calculator_id": "brick", "inputs": {…}}`

## Example

- 20 ft × 8 ft wall, US modular brick, 5 % waste: inputs `{"unit_system":"imperial","wall_length":20,"wall_height":8,"brick_size":"us_modular","waste_percent":5}` → `{"wall_area_ft2":160,"wall_area_m2":14.86,"bricks_per_ft2":6.75,"bricks_per_m2":72.66,"bricks_needed_no_waste":1080,"bricks_needed":1134,"mortar_volume_cubic_feet":9.46,"mortar_volume_m3":0.268,"mortar_bags_80lb":30,"mortar_bags_25kg":44}`
- 6 m × 2.4 m wall, UK standard brick, 5 % waste: inputs `{"unit_system":"metric","wall_length":6,"wall_height":2.4,"brick_size":"uk_standard","waste_percent":5}` → `{"wall_area_m2":14.4,"bricks_per_m2":59.26,"bricks_needed_no_waste":854,"bricks_needed":896,"mortar_volume_m3":0.254,"mortar_bags_80lb":24,"mortar_bags_25kg":35}`

```
GET https://tttkmbb.com/api/v1/calculate/brick?unit_system=imperial&wall_length=20&wall_height=8&brick_size=us_modular&waste_percent=5
```

## Limitations

The wall is concrete block (use the block face 440 × 215 mm or 8 × 16 in as a custom brick) or two leaves thick: double the brick count, or use concrete-slab for footings. Single-leaf stretcher bond only; the geometric mortar volume (≈ 0.018 m³ per m² for UK bricks, close to BIA's 5.5 ft³ per 100 ft² for modular brick) excludes frogs, perforations and dropped mortar, which is why bag counts use the manufacturer's per-brick rule instead. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**How many bricks per square metre?**

About 60 for UK bricks (215 × 65 mm with 10 mm joints gives 59.3), 50 for Australian and German formats, 73 for US modular (6.75 per ft²) and 75 for the 190 × 57 mm metric modular brick, all for a single leaf in stretcher bond.

**What about a full-brick (one-brick-thick) wall?**

Double the brick count (≈ 120 per m² for UK bricks) and roughly triple the mortar, because the collar joint between the two leaves is also filled.

**Why do the mortar volume and the bag count not match?**

The volume is the net geometry of the joints; the bag rule (37 bricks per 80 lb bag) is the manufacturer's practical figure and includes frogs, perforations and spillage, which typically double the mortar actually used.

## Related

- [Concrete Slab Calculator](https://tttkmbb.com/construction/concrete-slab.md) — Concrete for the footing under the wall.
- [Rectangle Calculator](https://tttkmbb.com/geometry/rectangle.md) — Area of a wall with openings to subtract.
- [Gravel Calculator](https://tttkmbb.com/construction/gravel.md) — Hardcore or sand under the footing.