Brick Calculator - calculatorpeak.com

About the Brick Calculator

Counting bricks for a wall sounds like simple division: the area of the wall divided by the area of a brick. Done that way, it is wrong by about a fifth, because it leaves out the mortar.

Every brick in a wall sits with a mortar joint along one end and along its top, so each brick effectively occupies its own face plus a joint in each direction. For a standard UK brick that turns 215 by 65 mm into 225 by 75 mm — and the familiar rule of 60 bricks per square metre falls straight out of it.

This brick calculator works from the wall's size, subtracts windows and doors, uses the brick size and joint you choose, doubles up for a double-skin wall and adds a waste allowance.

How to Use the Brick Calculator

Choose metric or imperial units.

Enter the wall's length and height, and the total area of any windows and doors in it.

Pick the brick size: UK standard, US modular or Euro format.

Choose single skin (half-brick, about 100 mm thick) or double skin (one-brick, about 215 mm thick).

Adjust the waste allowance — 5% is typical.

How the Brick Count Is Worked Out

  wall area        =  length × height − openings
  bricks per m²    =  1 ÷ ((brick length + joint) × (brick height + joint))
  bricks           =  wall area × bricks per m² × skins × (1 + waste %)

Step-by-Step Example

A 5 × 2 m wall with 1.5 m² of openings, UK bricks, single skin, 5% waste.

  Wall area:      5 × 2 − 1.5              =  8.5 m²
  Per m²:         1 ÷ (0.225 × 0.075)      =  59.3
  Bricks:         8.5 × 59.3               =  504
  With waste:     504 × 1.05               =  529 bricks

Where "60 per Square Metre" Comes From

A UK standard brick is 215 mm long and 65 mm high on its face. Laid with 10 mm joints, each brick takes up 225 by 75 mm of wall:

  1 m² ÷ (0.225 m × 0.075 m)  =  59.3 bricks

Without the joints, the same division gives 1 ÷ (0.215 × 0.065) = 71.6 — about 21% too many. That is why dividing a wall's area by a brick's face is such a common over-order.

Single and Double Skin

A single-skin wall is one brick laid lengthwise — about 100 mm or 4 inches thick. It is used for garden walls and as the outer leaf of cavity walls.

A double-skin or "one-brick" wall is two skins laid side by side, about 215 mm thick, and needs twice as many bricks. The two skins are tied together by the bond pattern — headers in English or Flemish bond run across both — or by wall ties. Whatever the bond, the number of bricks per square metre of wall face comes out the same: about 120 for UK bricks.

Waste, Cuts and Batches

About 5% extra covers bricks cut at corners, ends and openings, and the odd breakage. Walls with lots of openings, piers, curves or decorative cutting can need 10%.

Bricks also vary in colour between batches. Order enough from one batch to finish the job, and when laying, mix bricks from several packs so any variation is spread across the wall rather than showing as bands.

Mortar

Mortar is not included here, but it is closely tied to the brick count. A rough guide for UK bricks is about 0.02 to 0.03 m³ of mortar per square metre of single-skin wall. The mortar calculator gives a fuller figure with sand and cement quantities.

Walls With Piers and Corners

Real walls are rarely a plain rectangle, and a few features change the count.

Piers — thicker columns built into a long garden wall for stability — add bricks. Treat each pier as a short section of double-skin wall and add it separately.

Corners and returns use extra cut bricks to keep the bond, which is one reason walls with many corners need more waste.

Copings and caps along the top of a wall are often a different brick or stone, so count them separately.

Footings below ground are usually built in concrete blocks or engineering bricks rather than facing bricks. The block calculator covers those.

Dividing a complex wall into simple rectangles, working each out, and adding them up is the most reliable way to handle all of these.

Reclaimed Bricks

Reclaimed bricks are popular for matching older buildings, but they vary more in size and often need cleaning. Allow 10 to 15 per cent waste rather than 5, and check the actual size of a sample before relying on a standard rate per square metre.

Understanding Your Result

Bricks needed is the total including waste.

Wall area shows the area after subtracting openings.

Bricks per area gives the rate for the brick size you chose, including joints.

Breakdown shows the bricks for the wall and the waste on top.

Worth knowing covers bonding double-skin walls and batch colour.

When Should You Use This Calculator?

Planning a garden wall, extension or planter.

Checking a builder's estimate against the wall size.

Comparing brick sizes, as Euro and UK bricks give different counts.

Before ordering, so everything comes from one batch.

Common Mistakes

Ignoring the mortar joint. It overstates the count by about a fifth.

Forgetting openings. Large windows and doors save many bricks.

Counting a double-skin wall once. It needs twice as many.

Ordering exactly. Allow for cuts and breakage.

Ordering in stages. Later batches may not match in colour.