Why are there different types of bricks? To the average eye, most clay bricks might look the same with some visual variation. While it’s true that the spectrum of brick colours and textures is expansive, there are also important nuances below the surface. Depending on where you’re applying bricks, they’ll need to meet certain requirements to ensure the structure is safe, long-lasting and fits aesthetic standards where necessary or desired.
In this article, we’ll introduce you to the most common types of bricks, their key characteristics and their typical use cases.
Facing bricks
As the name suggests, facing bricks ‘face’ outwards. They’re the bricks we see day-to-day as they make up external walls and feature walls—anywhere where aesthetic is essential. They’re designed to look good, but that doesn’t mean they’re superficial. They still need excellent compressive strength, thermal performance and durability to be sustainable bricks that support long-lasting structures.
Within facing bricks, there are four main methods of manufacturing which produce different visual effects or designs:
- Extruded (or wirecut) bricks: These bricks are manufactured through an extrusion process. Clay is pushed through a shaped die on the end of an extruder, an industrial machine for processing clay brick mix. The continuous column of clay is then cut to size to make individual bricks using a sharp wire (hence wirecut), creating various profiles that can be either perforated (containing holes) or solid. These perforations reduce weight, aid thorough firing and lower fuel costs.
- Waterstruck bricks: This method uses water to prevent the clay from sticking as it’s pushed through rectangular dies. The water gives these bricks a rougher and more rustic texture than non-waterstruck bricks.
- Stock bricks: These are bricks with a frog—a hollow on one side of the brick to make it lighter. Clay will be thrown into a mould that creates the hollow, usually by a machine.
- Handmade bricks: These standard bricks are created by throwing sand-coated clay into a mould, with the sand acting as a lubricant. It also acts as a colourant for the brick face and influence its texture.
Facing bricks are the main focus of our product ranges at Michelmersh, from high-quality and high-volume for large housing projects to bespoke and handmade for specialist builds or refurbishment and stock for urban regeneration or education.
Engineering bricks
Less visible in our daily lives but imperative for our infrastructure are engineering bricks. Their manufacturing process gives them even more compressive strength and lower water absorption. This makes them ideal for groundworks and civil projects that involve consistent exposure to high pressures, low temperatures, water and chemicals. Examples include building foundations, tunnels, sewers and retaining walls.
There are two classes of engineering bricks for more or less extreme conditions:
- Class A engineering bricks’ compressive strength is greater than 125N/mm² and their water absorption is less than 4.5%.
- Class B engineering bricks’ compressive strength is greater than 75N/mm² and their water absorption is less than 7%.
Common bricks
Despite their name, common bricks have more limited applications than facing and engineering bricks. They’re usually cheaper to produce and buy because they’re composed of lower quality materials and use a less rigorous manufacturing process. As a result, they also typically have rougher texture and uneven finish and colour. But they’re ideal for use cases where you would typically apply a render on top such as partitioning walls or additional internal layers.
Special types of bricks
Some applications require specific designs or technical specifications, so you may also hear about the following types of bricks:
Special bricks (or brick specials) have a specific shape to meet certain architectural requirements. Angle bricks, bullnose bricks and soldier bricks are all types of special bricks. They’re either hand-thrown to specification or start life as an extruded or handmade brick and cut into their specific shapes afterwards.
Clay pavers are designed to be laid horizontally for flat surfaces, most often in areas of footfall or light vehicle traffic. They’re tested to different standards to other bricks to ensure they’re resistant to abrasion, frost, slipping and skidding and load-related breakage.
Air bricks can be made out of clay, but are also available in plastic and metal. They have multiple air circulation holes to provide ventilation and prevent dampness. They’re most commonly used in sub-floor voids under timber flooring to avoid damage from decay.
Fire bricks can withstand extremely high temperatures without damage thanks to their materials—typically alumina and silica. You’ll find them in industrial applications such as furnaces, incinerators and boiler linings as well as in residential and commercial applications such as chimneys, barbecues and pizza ovens.
Britain’s brick specialists
If you’re searching for more information about the best types of bricks to use on your project, we have multiple resources that can help. Our fully customisable Façade Designer tool allows you to create your own brick façade with our full range of products to visualise your perfect project. You can also learn more about clay bricks and get an accredited CPD certificate from our event ‘Right Brick, First Time’—contact us for more details and booking.
