Brickwork

 ( Bricks ) 

Brickwork is masonry produced by a bricklayer, using and mortar. Typically, rows of bricks called coursesJoseph Moxon. Mechanick Exercises: Or, The Doctrine of Handy-Works. Applied to the Arts of Smithing, Joinery, Carpentry, Turning, Bricklaying. Printed for Daniel Midwinter and Thomas Leigh. 1703. London. Page 129. "Three or four or five courses of Bricks to be laid."Nicholson. "By a Course, in walling, is meant the bricks contained between two planes parallel to the horizon, and terminated by the faces of the wall. The thickness is that of one brick with mortar. The mass formed by bricks laid in concentric order, for arches or vaults, is also denominated a Course." are laid on top of one another to build up a structure such as a brick wall.

Bricks may be differentiated from blocks by size. For example, in the UK a brick is defined as a unit having dimensions less than and a block is defined as a unit having one or more dimensions greater than the largest possible brick.

Brick is a popular medium for constructing buildings, and examples of brickwork are found through history as far back as the Bronze Age. The fired-brick faces of the ziggurat of ancient Dur-Kurigalzu in Iraq date from around 1400 BC, and the brick buildings of ancient Mohenjo-daro in modern day Pakistan were built around 2600 BC. Much older examples of brickwork made with dried (but not fired) bricks may be found in such ancient locations as Jericho in Palestine, Çatal Höyük in Anatolia, and Mehrgarh in Pakistan. These structures have survived from the Stone Age to the modern day. Brick dimensions are expressed in construction or technical documents in two ways as co-ordinating dimensions and working dimensions.

• Coordination dimensions are the actual physical dimensions of the brick with the mortar required on one header face, one stretcher face and one bed.
• Working dimensions is the size of a manufactured brick. It is also called the nominal size of a brick.

An example of a co-ordinating metric commonly used for bricks in the UK is as follows:Brunskill, p. 39. "British Standard 3921 of 1969, gave dimensions of 215 mm by 102.5 mm by 65 mm ...."British Standards Institution. Specification for Masonry Units. Part 1: Clay Masonry Units. BSI, London, 2003, BS EN 771.The Compressive Strength of Modern Earth Masonry, Andrew Heath, Mike Lawrence, Peter Walker and Clyde Fourie. BRE Centre for Innovative Construction Materials, University of Bath and Natural Building Technologies (NBT). Proceedings of the 11th International Conference on Non-conventional Materials and Technologies (NOCMAT 2009). 6–9 September 2009, Bath, UK. "All earth masonry units were intended to be 'standard' brick size (215x102.5x65mm) if they were fired, but because they did not have additional shrinkage from firing, the average size was 223x106x67mm."

• Bricks of dimensions 215 mm × 102.5 mm × 65 mm;
• Mortar beds (horizontal) and perpends (vertical) of a uniform 10 mm.

In this case the co-ordinating metric works because the length of a single brick (215 mm) is equal to the total of the width of a brick (102.5 mm) plus a perpend (10 mm) plus the width of a second brick (102.5 mm).

There are many other brick sizes worldwide, and many of them use this same co-ordinating principle.

• Top and bottom surfaces are called beds
• Ends or narrow surfaces are called headers or header faces
• Sides or wider surfaces are called stretchers or stretcher faces
  (2025). 9781405102100, Blackwell Publishing Ltd. ISBN 9781405102100

Mortar placed between bricks is also given separate names with respect to their position. Mortar placed horizontally below or top of a brick is called a bed, and mortar placed vertically between bricks is called a Perpend stone. A brick made with just rectilinear dimensions is called a solid brick. Bricks might have a depression on both beds or on a single bed. The depression is called a frog, and the bricks are known as frogged bricks. Frogs can be deep or shallow but should never exceed 20% of the total volume of the brick. Cellular bricks have depressions exceeding 20% of the volume of the brick. Perforated bricks have holes through the brick from bed to bed, cutting it all the way. Most of the building standards and good construction practices recommend the volume of holes should not exceed 20% of the total volume of the brick.

Parts of brickwork include bricks, beds and perpends. The bed is the mortar upon which a brick is laid.Nicholson, p. 166. "BED.—The under-surface of bricks when laid in any kind of work." A perpend is a vertical joint between any two bricks and is usually—but not always—filled with mortar.Reports of artisans selected by a committee appointed by the council of the Society of Arts to visit the Paris Universal exhibition, 1867. Published for the Society for the Encouragement of Arts, Manufactures and Commerce. Published by Bell and Daldy, York Street, Covent Garden, London. Printed by W.  Trounce, Cursitor Street, Chancery Lane, London. 1867. Part 1. Bricklaying by George Howell. Page 194. "The beauty of brickwork will very much depend upon the 'perpends' being perfectly kept, that is, the perfect regularity of the perpendicular joints right up the building."

A "face brick" is a higher-quality brick, designed for use in visible external surfaces in face-work, as opposed to a "filler brick" for internal parts of the wall, or where the surface is to be covered with stucco or a similar coating, or where the filler bricks will be concealed by other bricks (in structures more than two bricks thick).

Stretcher or stretching brick

Header or heading brick

Soldier

A brick laid vertically with its long narrow side exposed.Whitney Clark Huntington. Building Construction. Types of Construction, Materials, and Cost Estimating. New York

Sailor

A brick laid vertically with the broad face of the brick exposed.Sovinski, p. 43. "Those brick positions oriented in a horizontal alignment are called stretcher, header, rowlock stretcher, and rowlock. A rowlock stretcher is sometimes called a shiner. The two corresponding vertical orientations are the soldier and sailor positions."

Rowlock

A brick laid on the long narrow side with the short end of the brick exposed.Samuel Y. Harris. Building Pathology. Wiley. New York. 2001. Page 212. "The short face, or the end laid horizontally, is a header; laid vertically, a rowlock."

Shiner or rowlock stretcher

Occasionally, however, a brick must be cut to fit a given space or to be the right shape for some purpose — for example, creating an offset (a lap) at the beginning of a course.Charles F.Mitchell. Building Construction. Part 1. First Stage or Elementary Course. Second Edition—Revised. Published by B.T. Batsford, 52 High Holborn. 1889. Page 22. In some cases these special shapes or sizes are manufactured. In the diagrams below, some of the cuts most commonly used for generating a lap are coloured as follows:

A brick cut to three-quarters of its length, and laid flat with its long, narrow side exposed.

A brick cut to three-quarters of its length, and laid flat with its short side exposed.

A brick cut in half across its length, and laid flat.

A brick cut in half down its width, and laid with its smallest face exposed and standing vertically. A queen closer is often used for the purpose of creating a lap.Encyclopædia Britannica. 1911. BRICKWORK. "... portions of a brick ... a half header in width, ... are called queen closers."

Less frequently used cuts are all coloured as follows:

A brick cut to a quarter of its length.

A queen closer cut to three-quarters of its length.

A brick with one corner cut away, leaving one header face at half its standard width.Charles F.Mitchell. Building Construction. Part 1. First Stage or Elementary Course. Second Edition—Revised. Published by B.T. Batsford, 52 High Holborn. 1889. Page 18. "King Closers are bricks cut so that one end is half the width of a brick, and are used in positions where the greater width at back would add strength to the bond...."

Walls, running linearly and extending upwards, can be of varying depth or thickness. Typically, the bricks are laid also running linearly and extending upwards, forming or leafs. It is as important as with the perpends to bond these leaves together. Historically, the dominant method for consolidating the leaves together was to lay bricks across them, rather than running linearly.

Brickwork observing either or both of these two conventions is described as being laid in one or another bond.Nicholson, p. 347. "BRICKS ARE LAID in a varied, but regular, form of connection, or Bond, as exhibited in Plate LXXXV."Nicholson, p. 329. "BOND.—That regular connection, in lapping the stones upon one another, when carrying up the work, which forms an inseparable mass of building."

The thickness specified for a wall is determined by such factors as damp proofing considerations, whether or not the wall has a cavity, load-bearing requirements, expense, and the era during which the architect was or is working.Bricks and Brickwork. Cecil C. Handisyde and Barry A. Haseltine. The Brick Development Association. 19 Grafton Street, London, W1X 3LE. 1974. Page 68. "Old buildings of solid wall construction were accepted as 'waterproof', often when brickwork was only thick. Now it is generally agreed that solid walls of less than one brick thickness are inadequate. Code of Practice 121 still includes unrendered one brick thick walls as acceptable for sheltered positions but this seems a questionable recommendation. Walling of one brick thickness should be satisfactory for sheltered positions and may be adequate for moderate exposure."Emmitt, p. 206. "In exposed positions such as high ground and near the coast, a wall 2B thick may be needed to resist penetration to inside faces .... In positions of very severe exposure to wind-driven rain, as on high open ground facing the prevailing wind and on the coast facing open sea, it is necessary to protect both solid and cavity walls with an external cladding." Wall thickness specification has varied considerably, and while some non-load-bearing brick walls may be as little as half a brick thick, or even less when shiners are laid stretcher bond in partition walls, other brick walls are much thicker. The Monadnock Building in Chicago, for example, is a very tall masonry building, and has load-bearing brick walls nearly two metres thick at the base.Fuller, Chicago Tribune, December 7, 1958. The majority of brick walls are however usually between one and three bricks thick. At these more modest wall thicknesses, distinct patterns have emerged allowing for a structurally sound layout of bricks internal to each particular specified thickness of wall.

Despite there being no masonry connection between the leaves, their transverse rigidity still needs to be guaranteed.Emmitt, p. 7 The device used to satisfy this need is the insertion at regular intervals of wall ties into the cavity wall's mortar beds.Emmitt, pp. 232, 233. "Early cavity walls were constructed with bonding bricks laid across the cavity at internals to tie the two leaves together. ... Later, iron ties were used to tie the two leaves together."David Yeomans. Construction Since 1900: Materials. BT Batsford Ltd, 583 Fulham Road, London, SW6 5BY. 1997. . Page 60. "In 1974, a large section of the outer leaf of a wall of a comprehensive school at Newnham collapsed revealing a complete absence of ties over a considerable area and in 1983, a much larger section of a wall at Plymouth Polytechnic collapsed due to corrosion of the cavity ties."

Where a course begins with a quoin stretcher, the course will ordinarily terminate with a quoin stretcher at the other end. The next course up will begin with a quoin header. For the course's second brick, a queen closer is laid, generating the lap of the bond. The third brick along is a stretcher, and is—on account of the lap—centred above the header below. This second course then resumes its paired run of stretcher and header, until the final pair is reached, whereupon a second and final queen closer is inserted as the penultimate brick, mirroring the arrangement at the beginning of the course, and duly closing the bond.

Some examples of Flemish bond incorporate stretchers of one colour and headers of another. This effect is commonly a product of treating the header face of the heading bricks while the bricks are being baked as part of the manufacturing process. Some of the header faces are exposed to wood smoke, generating a grey-blue colour, while other simply vitrified until they reach a deeper blue colour. Some headers have a glazed face, caused by using salt in the firing. Sometimes Staffordshire Blue bricks are used for the heading bricks.Brunskill, pp. 57–58. Arch. Review, p. 233.

Brickwork that appears as Flemish bond from both the front and the rear is double Flemish bond, so called on account of the front and rear duplication of the pattern. If the wall is arranged such that the bricks at the rear do not have this pattern, then the brickwork is said to be single Flemish bond.Brunskill, p. 91. "SINGLE FLEMISH BOND: gives the appearance of Flemish Bond on the outside face only of a wall more than thick. The same appearance on both inner and outer faces is given by DOUBLE FLEMISH BOND."

Flemish bond brickwork with a thickness of one brick is the repeating pattern of a stretcher laid immediately to the rear of the face stretcher, and then next along the course, a header. A lap (correct overlap) is generated by a queen closer on every alternate course:

A simple way to add some width to the wall would be to add stretching bricks at the rear, making a Single Flemish bond one and a half bricks thick:

For a double Flemish bond of one and a half bricks' thickness, facing bricks and the bricks behind the facing bricks may be laid in groups of four bricks and a half-bat. The half-bat sits at the centre of the group and the four bricks are placed about the half-bat, in a square formation. These groups are laid next to each other for the length of a course, making brickwork one and a half bricks thick.Nicholson, p. 102. "... the bricks are disposed alike on both sides of the wall, the tail of the headers being placed contiguous to each other, so as to form square spaces in the core of the wall for half-bricks."Charles F.Mitchell. Building Construction. Part 1. First Stage or Elementary Course. Second Edition—Revised. Published by B.T. Batsford, 52 High Holborn. 1889. Page 25, figures 37 & 38.

To preserve the bond, it is necessary to lay a three-quarter bat instead of a header following a quoin stretcher at the corner of the wall. This fact has no bearing on the appearance of the wall; the choice of brick appears to the spectator like any ordinary header:

For a more substantial wall, a header may be laid directly behind the face header, a further two headers laid at 90° behind the face stretcher, and then finally a stretcher laid to the rear of these two headers. This pattern generates brickwork a full two bricks thick:

For a still more substantial wall, two headers may be laid directly behind the face header, a further two pairs of headers laid at 90° behind the face stretcher, and then finally a stretcher laid to the rear of these four headers. This pattern generates brickwork a full three bricks thick:

The great variety of monk bond patterns allow for many possible layouts at the quoins, and many possible arrangements for generating a lap. A quoin brick may be a stretcher, a three-quarter bat, or a header. Queen closers may be used next to the quoins, but the practice is not mandatory.

Occasionally, brickwork in such a raking monk bond may contain minor errors of header and stretcher alignment some of which may have been silently corrected by incorporating a compensating irregularity into the brickwork in a course further up the wall. In spite of these complexities and their associated costs, the bond has proven a common choice for constructing brickwork in the north of Europe.

Raking courses in monk bond may—for instance—be staggered in such a way as to generate the appearance of diagonal lines of stretchers. One method of achieving this effect relies on the use of a repeating sequence of courses with back-and-forth header staggering. In this grouping, a header appears at a given point in the group's first course. In the next course up, a header is offset one and a half stretcher lengths to the left of the header in the course below, and then in the third course, a header is offset one stretcher length to the right of the header in the middle course. This accented swing of headers, one and a half to the left, and one to the right, generates the appearance of lines of stretchers running from the upper left hand side of the wall down to the lower right. Such an example of a raking monk bond layout is shown in the New Malden Library, Kingston upon Thames, Greater London.

Elsewhere, raking courses in monk bond may be staggered in such a way as to generate a subtle appearance of indented pyramid-like diagonals. Such an arrangement appears in the picture here from the building in Solna, Sweden.

Many other particular adjustments of course alignment exist in monk bond, generating a variety of visual effects which differ in detail, but often having the effect of directing a viewing eye diagonally down the wall. Arch. Review, p. 241. THE BONDING OF BRICKWORK. P.M. Stratton. "Monk bond ... is popular in the North of Europe. Two stretchers are followed by one header in every course, the headers being so disposed that verticality of their axial lines is little apparent, and a striking result is obtained of diagonal lines of stretchers, which look like a series of corbels or cantilevers embedded in the wall."

The bond's horizontally extended proportion suits long stretches of masonry such as garden walls or the run of brickwork over a ribbon window; conversely, the bond is less suitable for a surface occupied by many features, such as a Georgian façade. The relatively infrequent use of headers serves to make Sussex bond one of the less expensive bonds in which to build a wall, as it allows for the bricklayer to proceed rapidly with run after run of three stretchers at a time. Arch. Review, p. 241. THE BONDING OF BRICKWORK. P.M. Stratton.

 File:Brickwork in english bond.svg |English bond
 File:Brickwork in english cross bond.svg |English cross bond
 File:Brickwork in double english cross bond.svg |Double English cross bond
     

One of the two kinds of course in this family of bonds is called a stretching course, and this typically comprises nothing but stretchers at the face from quoin to quoin. The other kind of course is the heading course, and this usually consists of headers, with two queen closers—one by the quoin header at either end—to generate the bond.Charles F.Mitchell. Building Construction. Part 1. First Stage or Elementary Course. Second Edition—Revised. Published by B.T. Batsford, 52 High Holborn. 1889. Page 23.

Large areas of English cross bond can appear to have a twill like characteristic, an effect caused by the unbroken series of perpends moving diagonally down the bond.

 File:Brickwork in english garden wall bond rake.svg |A raking English garden wall bond
 File:Brickwork in scottish bond.svg |Scottish bond
 File:Brickwork in american bond.svg |American bond
     

For the standard English garden wall bond, headers are used as quoins for the middle stretching course in order to generate the lap, with queen closers as the penultimate brick at either end of the heading courses. A more complex set of quoins and queen closers is necessary to achieve the lap for a raking English garden wall bond.

The heading course in English garden wall bond sometimes features bricks of a different colour to its surrounding stretchers. In English chalk districts, flint is substituted for the stretchers, and the headers constitute a lacing course.

The lap is generated by the use of headers as quoins for the even-numbered stretching courses, counting up from the previous heading course, with queen closers as the penultimate brick at either end of the heading courses.

Headers are used as quoins for the even-numbered stretching courses, counting up from the previous heading course, in order to achieve the necessary off-set in a standard American bond, with queen closers as the penultimate brick at either end of the heading courses.

The brick Clarke-Palmore House in Henrico County, Virginia, has a lower level built in 1819 described as being American bond of three to five stretching courses between each heading course, and an upper level built in 1855 with American bond of six to seven stretching courses between each heading course. and Accompanying four photos at Virginia Historic Landmarks Commission, undated

 File:Brickwork in heading bond.svg |Header bond
 File:Brickwork in stretching bond.svg |Stretcher bond
 File:Brickwork in stretching bond rake.svg |A raking stretcher bond
     

Header bond is often used on curving walls with a small radius of curvature. In Lewes, Sussex, England UK many small buildings are constructed in this bond, using blue coloured bricks and vitrified surfaces.Lloyd, p. 440. "HEADING BOND. All headers except a three-quarters brick at quoin in alternate courses." Arch. Review, pp. 242, 245. THE BONDING OF BRICKWORK. P.M. Stratton.

It is the simplest repeating pattern, and will create a wall one header thick.

 File:Brickwork in flemish stretcher bond.svg |Flemish stretcher bond
     

Flemish stretcher bond separates courses of alternately laid stretchers and headers, with a number of courses of stretchers alone. Brickwork in this bond may have between one and four courses of stretchers to one course after the Flemish manner.Brunskill, p. 52. The courses of stretchers are often but not always staggered in a raking pattern.