5.10 Clay briCk
Clay brickwork is made from selected clays that are moulded or cut into shape and fired in ovens. the firing process transforms the clay into a building component with high compressive strength and excellent weathering qualities, attributes that have been exploited for millennia to build structures ranging from single-storey huts to enormous viaducts. Clay brickwork is australia’s most widely used external cladding and loadbearing wall medium. Clay bricks are readily available, massproduced, thoroughly tested modular building components. Their most desirable acoustic and thermal properties derive from their relatively high mass. Clay bricks are generally affordable, require little or no maintenance and possess high durability and load bearing capacity. The use of clay brickwork is informed by extensive Australian research, manufacturing and construction experience.
PerFOrmaNCe summarY appearance
Clay brickwork is available in a wide variety of natural colours and textures derived from fired clay used in combination with cement mortar joints of various colours and finishes. Bricks remain stable and colour-fast and do not need to be rendered or painted. Clay brickwork is most commonly used uncoated to display the richness and texture of the material.
4455 Masonry units and segmental pavers and AS 3700 provides the means of determining the strength of clay brickwork walls when subjected to horizontal loads resulting from wind, earthquake or fire. [See: 5.5 Construction Systems]
Clay brickwork has high thermal mass. If a building with internal clay brickwork walls and concrete floors is subjected to a heating and cooling cycle that crosses the comfort zone, the brickwork and concrete will maintain a relatively stable level of heat energy for an extended period. In summer, they will remain relatively cool and in winter, the same building will remain relatively warm. [See: 4.9 Thermal Mass]
The high compressive strength of fired clay bricks has been exploited for millennia to build structures ranging from single-storey huts to massive public buildings and enormous bridges and viaducts. Clay brickwork walls can support relatively high loads such as suspended concrete slabs. Clay brickwork is commonly used in four storey construction and with suitable detailing can be used for load bearing walls in much higher buildings. Clay bricks are manufactured under close controls to the requirements of AS/NZS
5.10 Clay briCk
toxicity and breathability
Clay bricks are inert and are not prone to offgassing of volatile materials. Clay brickwork and its constituents are non-toxic, however when handling cement (used in the mortar) or cutting brickwork with a masonry saw, manufacturersí safety procedures must be observed to minimise the risk of skin irritation and lung damage.
Clay brickwork consists of dense inorganic materials that do not harbour vermin. Termite resistance may be achieved in a variety of ways, including proprietary termite barriers developed for use with clay brickwork.
Durability and moisture resistance
Clay brickwork is extremely durable. AS 3700 masonry structures tables provide the prescriptive requirements for bricks, mortar, built-in components and reinforcement to achieve various levels of durability. Clay brickwork walls resist the penetration of rainwater, including wind-driven rain, although they are not completely waterproof. Some moisture may eventually soak through the mortar joints. For this reason external clay brickwork is generally constructed as either cavity walling (two leaves of brickwork separated by ties) or brick veneer (one leaf of brickwork separated from, but tied to a structural frame – may be reversed). Detailing for clay brickwork needs to incorporate: > Damp-proof courses. > Flashings. > Weep holes.
reverse brick veneer