For thousands of years, the elements of fire, water, air, and earth have been used to produce a building material of incomparable usefulness and attractiveness. Clay brick, as a natural and sustainable building material, can also contribute to a healthy indoor climate conducive to well-being
Nowadays most bricks in the UK are made to a standard brick size of 215mm long, 102.5mm wide and 65mm high (with alternative size options available) and laid with a nominal 10mm mortar joint.
Produced using a centuries old manufacturing process, handmade bricks offer a gently creased texture, an irregular shape and an indent in the top of the brick known as a “frog”.
At a rate of around 100 bricks per hour, the hand maker forms a roughly shaped clot which is then coated with sand and thrown into a pre-sanded mould box. The sands helped release the clay from the mould. A kicker is placed on the bottom of the mould to form a frog, which helps to spread the clay into the corners, aiding the drying and firing process.
Stock bricks, also known as soft mud, have a more traditional or reclaimed appearance, offering a softer and warmer brick aesthetic.
Soft mud brick moulding covers a number of automated manufacturing processes where bricks are formed using mould boxes. Machine manufacturing of soft mud bricks follows the processes of hand making, recreating the hand thrown technique by throwing the clay into sanded moulds using belts.
Waterstruck soft mud bricks are made by using water instead of sand to release the clay from the moulds, creating a distinctive textured finish.
Waterstruck bricks have a unique texture as a result of the use of water within the moulding and demoulding process.
Using a traditional softmud process, wet clay is pressed into moulds lubricated with water to prevent sticking. Excess clay is then struck from the top of the moulds, hence the term “waterstruck”. This produces a distinctive natural texture and a striking rustic aesthetic unachievable through any other manufacturing process. They are often solid bricks although some waterstruck bricks do have frogs.
The wirecut, or extruded, method is popular as it allows for a high volume of bricks to be manufactured quickly, around 20,000 bricks an hour. The clay is driven through an extrusion head to form a continuous column. The column is then cut into smaller, more manageable pieces approximately 1.5m in length known as ‘slugs’, which are cut into bricks of the desired length by row wires.
This manufacturing process produces hard, dense bricks with a consistent size and shape, sharp arises and a contemporary appearance.
Made using the same process as wirecut bricks, engineering bricks are selected for their enhanced technical performance rather than their appearance.
They are traditionally used in civil engineering and are most suitable for applications where strength and resistance to frost attack and water are important.
Engineering bricks are rated as Class A or Class B, with Class A being the strongest but Class B being more common. Class A bricks have a compressive strength greater than 125N/mm² and water absorption less than 4.5%. Class B bricks have a compressive strength greater than 75N/mm² and water absorption less than 7%.
Long Format Bricks
When it comes to making a design statement in construction, the use of different brick sizes offers exciting opportunities to create truly spectacular projects. A growing number of architects and designers are looking to use more unusual or uncommon brick dimensions, beyond the standard 215 x 65mm, to make their projects stand out from the crowd.
Long format bricks essentially offer a longer, leaner look than standard UK format bricks. For example, Wienerberger’s Roman bricks are available in size formats from 400 x 40mm up to 510 x 40mm.
At Wienerberger we’re proud to offer the widest range of bricks available in the UK, with hundreds of different colours, textures, styles and shapes to choose from, we’re confident that you’ll find the right brick for your project.
Visit www.wienerberger.co.uk to view the full collection and order a sample.