Although timber frame construction (and SIPs – see later for more details) is now claiming a growing share of the housing market, brickwork is still a major element in most houses/extensions. All brick and block walls should be built to a recognized bond. On external walls built in facing brick or selected commons the evenness of the bond is essential for appearances sake. (On walls that have a rendered finish, the neatness of the bonding is not so essential but the basics of bonding must be adhered to for stability. See Figs 8.3 to 8.9.)
TRADITIONAL EXTERNAL WALLS GENERALLY
As indicated above, although timber frame construction is now starting to displace standard brickwork, most external walls to modern domestic properties built in England and Wales are still of cavity wall construction. Although there had been some experimentation with cavity construction during the nineteenth century, cavity walls became more common at the beginning of the twentieth century in an attempt to overcome one of the major problems being experienced with solid walls, namely damp penetration. Because stretcher bond is simple to use with cavity walls, it is the form of
bonding most commonly seen on the external walls of modern housing (see Fig. 8.3). However, there are other bonds (e.g. English bond (Fig. 8.4), English garden wall bond (Fig. 8.5) and Flemish bond (Fig. 8.6)). When you are carrying out your survey prior to preparing plans, note the brick bonding on the existing building. The bonds shown usually give a strong indication of the existing wall construction. Stretcher bond usually indicates that the walls are of cavity construction (but not always). English bond, Flemish bond and English garden wall bonds usually indicate solid wall construction. The subject of bond is discussed in greater detail in Chapter 8 (section on Matching materials). Solid walls can still be used in modern construction, but now a water-
repellent defence has to be installed (e.g. external tile hanging or external rendering). As the cavity wall is now the most common, I intend to concentrate on this form of construction.