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The history of brickwork as detailed in books by authors such as Nicholas Pevsner and Nathaniel Lloyd highlights the huge variety of sizes and formats of brick that have been used over time. Handmade brick are often preferred over normal machine-made brick because they offer more flexibility for conservation or consistency purposes. Texture is also an important issue, and it can vary from a very smooth brick, exemplified by the famous Williamson Cliff range used on Oxbridge Colleges and Buckingham Palace, to a rougher, more textured brick. The smoothness or weathered look can be affected by the dampness in the sand and the speed at which the brick are manufactured.
Advances in technology have led to cheaper and more efficient manufacturing techniques, yet handmade brick are still popular for aesthetic reasons. Several factors make handmade brick different than machined brick, especially in the areas of forming, setting and firing, and blending.
FormingIt would be difficult to produce more than 1000 traditional bench-made, handmade brick per day, since they are made one at a time. The maker has to sand the mold by hand, prepare the clay and throw it into the mold, cut off the surplus with a bow and turn the mold over, emptying it onto a tray for drying.
Such a slow operation means that a handmade brick producer is lucky to make 100 brick an hour. However, the brick are neat and tidy, and they have arrises at least as good as machine-made brick. In addition, the molds in which handmade brick are formed are inherently flexible, so brick can be manufactured in virtually any size from 300 x 135 x 90 mm down to 40 x 100 x 35 mm (briquette), depending on the type of clay.
With the use of a mechanized hand-thrown system known as a circuit, where the maker throws the clay into the mold and the machine does the rest, up to 30,000 brick per day may be produced by a five-man team. The brick are more distressed and rougher looking, but the color and the effect can be very attractive.
Handmade brick “specials” can be more easily manufactured than machine-made brickwork. The process generally just requires a mold and a knowledgeable operator to allow all varieties and shapes to be produced in a fairly economic manner. However, a first-class joiner is an essential element. The crafting of a feature mold for a special integral to the design of the brickwork requires consummate skill.
Setting and FiringTo understand how handmade brick achieves its originality, it is necessary to look at one of the basic aspects of production, the setting pattern in the kiln. Setting with a robotic or mechanized setting machine cannot be used when producing a traditional handmade clamp-fired look, which many conservators or new home builders want to replicate. Regular, even setting cannot produce the variation in color that is found in brick that was fired in clamps.
To achieve the proper aesthetics, the brick must be packed very densely so it is impossible to get the fire evenly through the brick. Nevertheless, in a modern intermittent kiln it is possible to ensure that the firing, if not the color, is consistent, which was not something that was possible for the clamp-fired brick of old.
BlendingWhen the brick come out of the kiln, it is important that they are blended because the middle of a dense pack of brick will be a different color than the brick on the outside of the pack (as a result of the difference between reduction and oxidization). A particular building or client may require a dark, weathered look but also need to incorporate red or pink parts. This can be achieved by putting parts of the color blend into a sorting system, ensuring a random mix of color around the pack, and manually mixing rather than robotic mixing or de-hacking.
The benefit of this method is that mixing from more than one pack is not required on-site; the brick have already been mixed in the factory before they reach the site. This advantage in productivity is more important than ever on building sites. The result is a brick wall that is more alive and interesting than one made by modern machines. Every clay building has its own appeal, but handmade brick offer a traditional look from the start.
Case in PointYork Handmade Brick Co., Alne, North Yorkshire, UK, recently supplied 100,000 special-sized and special-textured brick for the restoration of the iconic Murrays’ Mills in Ancoats, Manchester. Murrays’ Mills, built at the beginning of the industrial revolution, is the oldest surviving steam-powered cotton mill in the city. At its peak, Murrays’ Mills was a marvel, with visitors coming from the rest of Britain, Europe and America to see this vast building, illuminated by gaslight and operated by 1300 men, women and children.
York Handmade manufactured new brick to match the old building. Particularly difficult to replicate because of their unique nature, the original brick had been handmade on-site from clay excavated from the canal basin itself, with variable quality and bespoke size.
“We were able to emulate the appearance of these original brick using a mix of three brick types at a standard agreed size,” said David Armitage, chairman of York Handmade. “The new brick were used for individual brick replacements, local re-building in numerous areas, and the reinstatement of the missing upper stories of the Murray Street Block North.”
The restoration of Murrays’ Mills was carried out by Ancoats Buildings Preservation Trust, and the project was financed by the Heritage Lottery Fund and the North West Development Agency. The architect was Manchester-based BDP. When the new “mill” is complete (hopefully by next year), it will comprise 110 new apartments, a 60-bed hotel and 48,000 square feet of office space.
“In total, we used about 100,000 brick in this project, and we are absolutely delighted with the result,” said Armitage. “Murrays’ Mills has been restored to its former glory and is ready for the many new challenges of the 21st century.”
For additional information regarding handmade brick, contact York Handmade Brick Co. at (44) 01347-837202, e-mail email@example.com or visit www.yorkhandmade.co.uk.