page_title: Brick
section_title: Optimal dimensions, characteristics, and strength
hierarchical_section_title: Brick / Optimal dimensions, characteristics, and strength
caption_attribution_description: English: Vault of roman bath in Bath, England
context_page_description: A brick is a type of block used to build walls, pavements and other elements in masonry construction. Properly, the term brick denotes a block composed of dried clay, but is now also used informally to denote other chemically cured construction blocks. Bricks can be joined together using mortar, adhesives or by interlocking them. Bricks are produced in numerous classes, types, materials, and sizes which vary with region and time period, and are produced in bulk quantities.
  Block is a similar term referring to a rectangular building unit composed of similar materials, but is usually larger than a brick. Lightweight bricks are made from expanded clay aggregate.
  Fired bricks are one of the longest-lasting and strongest building materials, sometimes referred to as artificial stone, and have been used since circa 4000 BC. Air-dried bricks, also known as mudbricks, have a history older than fired bricks, and have an additional ingredient of a mechanical binder such as straw.
  Bricks are laid in courses and numerous patterns known as bonds, collectively known as brickwork, and may be laid in various kinds of mortar to hold the bricks together to make a durable structure.
context_section_description: For efficient handling and laying, bricks must be small enough and light enough to be picked up by the bricklayer using one hand (leaving the other hand free for the trowel). Bricks are usually laid flat, and as a result, the effective limit on the width of a brick is set by the distance which can conveniently be spanned between the thumb and fingers of one hand, normally about 100 mm (4 in). In most cases, the length of a brick is twice its width plus the width of a mortar joint, about 200 mm (8 in) or slightly more. This allows bricks to be laid bonded in a structure which increases stability and strength (for an example, see the illustration of bricks laid in English bond, at the head of this article). The wall is built using alternating courses of stretchers, bricks laid longways, and headers, bricks laid crossways. The headers tie the wall together over its width. In fact, this wall is built in a variation of English bond called English cross bond where the successive layers of stretchers are displaced horizontally from each other by half a brick length. In true English bond, the perpendicular lines of the stretcher courses are in line with each other.
  A bigger brick makes for a thicker (and thus more insulating) wall. Historically, this meant that bigger bricks were necessary in colder climates (see for instance the slightly larger size of the Russian brick in table below), while a smaller brick was adequate, and more economical, in warmer regions. A notable illustration of this correlation is the Green Gate in Gdansk; built in 1571 of imported Dutch brick, too small for the colder climate of Gdansk, it was notorious for being a chilly and drafty residence. Nowadays this is no longer an issue, as modern walls typically incorporate specialised insulation materials.
  The correct brick for a job can be selected from a choice of colour, surface texture, density, weight, absorption, and pore structure, thermal characteristics, thermal and moisture movement, and fire resistance.
  In England, the length and width of the common brick has remained fairly constant over the centuries (but see brick tax), but the depth has varied from about two inches (about 51 mm) or smaller in earlier times to about two and a half inches (about 64 mm) more recently. In the United Kingdom, the usual size of a modern brick is 215 × 102.5 × 65 mm (about ​8 ⁵⁄₈ × ​4 ¹⁄₈ × ​2 ⁵⁄₈ inches), which, with a nominal 10 mm (​³⁄₈ inch) mortar joint, forms a unit size of 225 × 112.5 × 75 mm (9 × ​4 ¹⁄₂ × 3 inches), for a ratio of 6:3:2.
  In the United States, modern standard bricks are specified for various uses; most are sized at about 8 × ​3 ⁵⁄₈  × ​2 ¹⁄₄ inches (203 × 92 × 57 mm). The more commonly used is the modular brick ​7 ⁵⁄₈  × ​3 ⁵⁄₈  × ​2 ¹⁄₄ inches (194 × 92 × 57 mm). This modular brick of ​7 ⁵⁄₈ with a ​³⁄₈ mortar joint eases the calculation of the number of bricks in a given wall.
  Some brickmakers create innovative sizes and shapes for bricks used for plastering (and therefore not visible on the inside of the building) where their inherent mechanical properties are more important than their visual ones. These bricks are usually slightly larger, but not as large as blocks and offer the following advantages:
  A slightly larger brick requires less mortar and handling (fewer bricks), which reduces cost
  Their ribbed exterior aids plastering
  More complex interior cavities allow improved insulation, while maintaining strength.
  Blocks have a much greater range of sizes. Standard co-ordinating sizes in length and height (in mm) include 400×200, 450×150, 450×200, 450×225, 450×300, 600×150, 600×200, and 600×225; depths (work size, mm) include 60, 75, 90, 100, 115, 140, 150, 190, 200, 225, and 250. They are usable across this range as they are lighter than clay bricks. The density of solid clay bricks is around 2000 kg/m³: this is reduced by frogging, hollow bricks, and so on, but aerated autoclaved concrete, even as a solid brick, can have densities in the range of 450–850 kg/m³.
  Bricks may also be classified as solid (less than 25% perforations by volume,
caption: Brick arch from a vault in Roman Bath – England
exif: {"Image Make": "Canon", "Image Model": "Canon EOS 350D DIGITAL", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2006:08:12 01:18:37", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "196", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "1660", "Thumbnail JPEGInterchangeFormatLength": "10981", "EXIF ExposureTime": "1/160", "EXIF FNumber": "28/5", "EXIF ISOSpeedRatings": "1600", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2006:08:12 01:18:37", "EXIF DateTimeDigitized": "2006:08:12 01:18:37", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "239925/32768", "EXIF ApertureValue": "162885/32768", "EXIF ExposureBiasValue": "0", "EXIF Flash": "Flash fired, compulsory flash mode", "EXIF FocalLength": "22", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2304", "EXIF ExifImageLength": "3456", "EXIF FocalPlaneXResolution": "1728000/437", "EXIF FocalPlaneYResolution": "384000/97", "EXIF FocalPlaneResolutionUnit": "2", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard"}