Bond patterns in brickwork

The simple, regular form of a brick is very versatile and allows a great number of bond patterns to be used. A few are distinctive, widely used and have names that are commonly recognised. The previous article on bonding in Brick Bulletin (January 2005) discussed the basic patterns used in traditional and contemporary brickwork. Many variations of the basic bonds have been devised, principally to give variety in the appearance of facing brickwork.

In a few instances, bonding patterns have been developed in response to practical considerations. For example, to economise on the quantity of bricks used, rat-trap bond was devised. In its simplest form it is a variation of Flemish bond for use in one-brick-thick walls (215 mm), but in place of stretchers, the bricks

are laid on edge to show bed faces, alternating with headers on edge. There are hollow spaces behind the stretchers, which were left to give the walling greater resistance to rain penetration and heat loss. For obvious reasons perforated bricks are unsuitable. There are variations that involve bricks laid normally (flat) between courses of bricks laid on edge; this form is known as Silverlock’s bond, or Dearne’s bond. These hollow wall bonds were introduced in the 19th century for modest houses and garden walls. Modern uses tend to be confined to freestanding walls.

Properly set out and neatly built, all bonds can produce an attractive appearance. However, large areas of plain brickwork give an opportunity to exploit the more decorative potential of bonding. Frequently the effects are subtle, but when combined with the use of bricks of contrasting colour, striking effects are possible.

Herringbone panels

Between the stud members of traditional hardwood timber framed buildings brickwork is commonly seen as infill panels. Sometimes it is a replacement for less durable wattle and daub, but it can also be contemporary with the framework. Because such panels are normally only half a brick in thickness and have no loadbearing function in terms of the stability of the structure, they are frequently built as decorative features – herringbone patterns being very typical.

Herringbone and basketweave patterns are sometimes used as feature panels within plain bonded brickwork. They are usually formed as the half-brick outer leaf of a cavity wall or as a half-brick surface layer of thicker brickwork. In either case, ties should be used in the joints to secure the panel to the associated backing masonry. Stainless steel wire is recommended for modern applications.

Large-scale effects

Several bonds only achieve their full effect when used on a large area because their distinctive pattern is enhanced by multiple repetitions. For example, in two or three storeys of plain brickwork in English cross bond, a subtle diagonal criss-cross can be seen. Some more decorative bonds depend on multiple repetitions of groups of several courses to generate their effects. Many are characterised by strong diagonal motifs and are referred to as “flying” bonds.

It will be obvious that elaborate bonding is likely to present difficulties when openings, piers and short lengths of brickwork have to be accommodated. Where these features occur, it is generally preferable to adopt a simpler bond and restrict the elaborate bonding to unencumbered major areas.

Projection

Projection of bricks from the general surface, individually or in whole courses, can produce striking three-dimensional characteristics. Projections need not be large; quite small overhangs have a disproportionate effect, especially in strong lighting. Stability must be considered and stainless steel wire in mortar joints can be used to reinforce or tie back projected work.

Idiosyncratic examples

For aesthetic reasons, some designers follow the general principles of bonding and create brickwork of unique appearance.

Specially designed bonded brickwork can also embody recessed and projected brick faces to produce highly modelled surfaces.

Although some examples of especially decorative work may give the impression of being extemporised and created freehand, in practice that is rarely, if ever, the case. Detailed design on paper, preliminary discussion with the bricklayer and trials followed by skilful attentive bricklaying are essential.