Home & DIY calculator

Mortar Calculator (for Brick)

Enter your wall size and brick size to get bricks and mortar bags needed.

Your measurements

Metric + imperial

How this calculator works

Bricks per m2 = 1 / [(brick length + joint) x (brick height + joint)]. Bricks = round up(wall area x waste factor x bricks per m2). Mortar volume = wall area x waste factor x mortar-per-m2 rule of thumb. Bags = round up(mortar liters / bag yield).

Worked example

A 5 m x 2 m wall face (10 m2, 10% waste = 11 m2) with a standard UK brick (215 x 65 mm, 10 mm joint) needs about 652 bricks and 27 bags of mortar at a 30 L/m2, 12.5 L/bag rule of thumb.

Assumptions to check

  • This is for a single skin (half-brick, stretcher-bond) brick wall face, not a cavity wall, block wall, or patio - use a separate mortar figure for block or patio laying, which use different joint and bedding conventions.
  • Mortar-per-m2 is an editable rule of thumb, not a joint-by-joint volume model, because real consumption depends heavily on wall thickness and joint width.
  • Wastage covers broken bricks, cut bricks at wall ends, and mixing losses.

Common questions

FAQ

Why "for brick" specifically?

Block and patio-laying mortar use different bedding thicknesses and coverage rates, so this tool is scoped to brickwork - use the mortar-per-m2 field to adjust if your own project differs.

What UK brick size does this default to?

A standard UK brick face is commonly 215 x 65 mm with a 10 mm joint, giving a 225 x 75 mm work size - both fields are editable for other sizes.

Does this include a corner or return wall?

No - this models one straight wall face (length x height). Add other wall faces as separate calculations.