Background and history
Bricks mainly fall into three categories: handmade, wirecut and machine made.
Handmade bricks have been in use from Roman times to the present day, but most of the reclaimed handmade bricks stocked in salvage yards come from Victorian buildings. Earlier handmade bricks were thinner, and these are generally still the most expensive. The reason for this thinness was that wood-fired clamps could only reliably fire bricks up to a certain thickness. In Georgian times brick sizes were regulated by tax and statute, but they gradually became thicker when reused sieved cinder, known as breeze, saved by night men from household fire ash, was mixed with the brick clay allowing for a more even firing in the middle of the brick.
The Victorians began to mechanise the aeration of clay, known as pugging, and this was quickly followed by the automated extrusion of a brick section which was then cut into bricks with a cheesewire frame, hence ‘wirecut’. By 1890 wirecut bricks were very common, and most reclaimed wirecut bricks date from 1890 to 1940, by which time wirecut production had virtually ceased. Wirecut bricks are generally thicker than handmades and included breeze as standard. Kiln technology had also moved on from clamps to more controllable coal-fired down-draught kilns and continuous tunnel kilns.
Most handmade and wirecut bricks are tough and were laid in comparatively weak lime mortar, so they are relatively easy to reclaim without being broken, if walls are carefully dismantled by hand.
The term ‘machine made brick’, sometimes called ‘pressed brick’, is given to bricks formed by the slop moulding process. Where clay is watered down into a creamy consistency and poured into moulds from which the water is squeezed, under high pressure, before firing occurs, usually in continuous tunnel kilns. Evenness of firing is helped by deep frogs which reduce the clay thickness in the centre of the brick. Fletton bricks are comparatively weak ‘biscuit fired’ bricks that are made from oil shale as opposed to brick clay. The oil has a fuel value that is used during firing. Most modern bricks are made using chemically tinted oil shales using the slop moulded high pressure process and oil-fired kilns.
Machine made bricks made after 1940 was usually set in a Portland cement mortar, which is harder than the comparatively weak brick. Such bricks are generally much harder to salvage because the bricks break more easily during the process to remove and clean them.
Sourcing Reclaimed Bricks
Reclaimed bricks have traditionally been used for older or listed properties where accurate matching is essential on extensions and renovations and for whole buildings in historical areas where older bricks are more in keeping.
Low end bricks are commonly flettons and wire cut bricks that are found all over the country. Regional bricks such as Staffordshire Blue or Luton Grey and Red are frequently at the top end of the price scale. Smaller (2”) bricks are more difficult to source and so tend to command a higher price.
Bricks vary in the clay types used and, therefore colour depending on the region. An array of colours are available, from rich reds to vibrant yellows. To some extent, the bricks at your local reclamation yard will likely reflect the prevalent hue in your region.
Specification
Most reclaimed bricks are approximately 9” (230mm) in length and 4.5” (110mm) in width. Height dimensions vary between 2” and 3”. Typical heights quoted are: 2”, 25/8”, 27/8”, 3”, 31/4”. This wide variety of sizes introduces problems in the specification of reclaimed bricks.
Reclaimed bricks are usually supplied without certification; most dealers grade the reclaimed bricks by quality of appearance but do not guarantee durability, though some salvage dealers will test frost heave and water absorption.
Remember to specify the use of lime or low cement mortars to enable future reuse of bricks.