Last edited 07 Feb 2018

Types of brick

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Contents

[edit] Introduction

Bricks are small rectangular blocks that can be used to form parts of buildings, typically their walls. Bricks are most typically made from clay, although they are also commonly made from calcium-silicate and concrete.

There are many different types of brick and these are categorised in various ways.

[edit] Method of manufacture

[edit] Common burnt clay bricks

Soft mud or dry-press bricks are formed by pressing the brick mixture into moulds and then firing them in a kiln. Soft-mud bricks are made from a thin mix whereas dry-press bricks are made from a thicker mix that gives crisper definition. Greater strength is achieved by using greater force when pressing the brick and by firing it for longer, but this increases the cost.

These can be categorised further as:

  • First class: Table-moulded and burnt in kilns, with smooth and straight surfaces.
  • Second class: Ground-moulded and burnt in kilns, with rough and irregular surfaces. Often used with plaster coating.
  • Third class: Ground-moulded and moulded in kilns. Used for temporary structures.
  • Fourth class: Over-burnt with irregular shape. Used as aggregate for concrete in foundations, floors, and so on.

[edit] Sand lime bricks

These are manufactured by mixing sand, fly ash and lime. The brick is then formed by moulding the mix under pressure. This can achieve a smoother finish and a more uniform shape than clay bricks.

[edit] Engineering bricks

Engineering bricks are both dense and strong as they are manufactured at very high temperatures. This also means they have excellent load-bearing capacity, damp-proof and chemical-resistant properties. These advantages mean they are generally used for civil engineering applications such as groundworks, sewers, retaining walls, and so on.

[edit] Concrete bricks

These are made from solid concrete and can be used above and below damp-proof course level. They can also be manufactured in different colours if pigment is added during production.

[edit] Fly ash clay bricks

This type of brick is manufactured with fly ash, cement, sand and water at about 1,000°C. Due to the high concentration of calcium oxide in fly ash, it is described as ‘self-cementing’.

[edit] Shape

Bricks can also be categorised according to their shape:

  • Airbrick: Contain holes to allow the circulation of ‘fresh’ outside air beneath suspended floors and within cavity walls.
  • Bullnose: Moulded with a rounded angle.
  • Channel: Moulded to the shape of a channel or gutter and often used as drains.
  • Coping: Used to cap the tops of parapets or freestanding walls, typically projecting at least 40 mm beyond both faces of the wall.
  • Capping: Also used to cap the tops of parapets or freestanding walls, but these sit flush with the vertical face of the wall.
  • Cownose: Moulded with a double bullnose on the end.
  • Curved sector: Curved for use in the construction of pillars, chimneys, columns, and so on.
  • Hollow: These are around one-third of the weight of ordinary bricks and are often used in partitions.
  • Perforated: Contain cylindrical holes and are often used in lightweight structures.
  • Purpose-made: For specific purposes, such as splay and cant bricks for door and window jambs, ornamental bricks, and so on.
  • Brick veneers / brick slips: These are thin bricks that can be used for cladding.
  • Radial, tapered or arch bricks.
  • Angle and cant bricks that form returns and chamfers.
  • Cill bricks.
  • Plinth bricks.
  • Soldier bricks, that form returns for soldier courses.

[edit] Find out more

[edit] Related articles on Designing Buildings Wiki