How many bricks are in a square metre in the UK?

A standard UK brick (215mm x 65mm x 102.5mm) with a 10mm mortar joint requires exactly 60 bricks per square metre (m2) of wall. This assumes a single-skin 'stretcher bond' layout.

How many blocks are in a square metre?

A standard UK concrete block (440mm x 215mm x 100mm) with a 10mm mortar joint requires 10 blocks per square metre (m2). Because blocks are much larger than bricks, they are faster to lay but much heavier.

What is the standard mortar mix for brickwork?

For most general masonry, a mix of 1 part cement to 4 or 6 parts sand is used. For modern house building, a pre-mixed mortar with plasticiser is often used to improve workability and frost resistance.

What are 'Thermal' or 'Aircrete' blocks?

Aircrete blocks (like Celcon or Thermalite) are lightweight blocks that contain thousands of tiny air bubbles. These provide excellent thermal insulation for the inner leaf of a cavity wall, helping the building meet modern energy efficiency regulations.

How many bricks are in a square metre in the UK?

A standard UK brick (215mm x 65mm x 102.5mm) with a 10mm mortar joint requires exactly 60 bricks per square metre (m2) of wall. This assumes a single-skin 'stretcher bond' layout.

How many blocks are in a square metre?

A standard UK concrete block (440mm x 215mm x 100mm) with a 10mm mortar joint requires 10 blocks per square metre (m2). Because blocks are much larger than bricks, they are faster to lay but much heavier.

What is the standard mortar mix for brickwork?

For most general masonry, a mix of 1 part cement to 4 or 6 parts sand is used. For modern house building, a pre-mixed mortar with plasticiser is often used to improve workability and frost resistance.

What are 'Thermal' or 'Aircrete' blocks?

Aircrete blocks (like Celcon or Thermalite) are lightweight blocks that contain thousands of tiny air bubbles. These provide excellent thermal insulation for the inner leaf of a cavity wall, helping the building meet modern energy efficiency regulations.

Brick & Block Calculator

Calculate masonry units for walls and extensions.

Total Wall Area (m²)

Material Type

Quantity Order

Masonry Tip: When ordering bricks, try to order the full amount from the same 'batch' or 'firing'. Bricks are natural products and colours can vary significantly between different production runs. Mixing packs as you build (known as 'blending') is also recommended to avoid colour banding.

Solid Walls: The UK Masonry Guide

Standardised Dimensions

Brickwork in the UK has been standardised for decades to ensure that bricks and blocks 'bond' correctly. The height of one block (215mm) is exactly equal to the height of three bricks including their mortar joints.

Our **brick and block calculator** uses these industry-standard ratios to give you an accurate order list, accounting for the unavoidable waste caused by cutting at corners and window openings.

Unit Specifications

Standard Brick215 x 65 x 102.5mm

Standard Block440 x 215 x 100mm

Mortar Joint10mm (Standard)

Cavity Walls & DPC

Most modern UK houses are built with **cavity walls**—an outer leaf of facing bricks and an inner leaf of concrete blocks, separated by a 100mm gap filled with insulation. The two leaves are held together by stainless steel 'wall ties'.

A **Damp Proof Course (DPC)** must be installed at least 150mm above ground level. This is a waterproof plastic or bitumen strip that prevents moisture from the ground rising up through the brickwork into the internal walls.

Efflorescence

New brickwork often develops white, powdery patches known as 'efflorescence'. This is simply natural salts in the clay reacting with water and is usually harmless. It will typically wash away naturally after a few heavy rains.

Frost Protection

Never lay bricks or blocks in freezing temperatures. If the water in the mortar freezes before it sets, it will expand and weaken the joint, potentially causing the wall to become unstable or collapse.

Pro Tip: Blending Packs

To avoid large patches of slightly different coloured bricks (known as banding), always open at least **three different packs** of bricks at the same time. Draw bricks from each pack diagonally to ensure any subtle shade variations are blended naturally across the entire wall.

Masonry & Brickwork FAQ

Project Disclaimer

Wall stability is dependent on proper foundations and structural design. For walls over 1 metre high, or any structural extension, consult a qualified architect or structural engineer. Ensure all masonry meets local UK Building Regulations.