Bricks and their different applications
There are many thousands of different types of bricks, they cover an ever increasing range of colours and finishes but they can be broken down into a handful of basic types. The majority of these bricks are made from clay and are fired in a kiln.
Brick Extrusion Process
The brick extrusion process used to create bricks involves the raw clay and other materials being pushed or drawn through a die of the desired cross section to achieve the brick shape.
So what are the different types of bricks available?
Facing Bricks
These are a high quality and durable brick with a rather attractive appearance. These bricks tend to be for external use above ground level.
Wirecut Bricks
The brick clay is continuously extruded to the required size and shape and then cut into individual bricks by means of a wire. Wires are used extensively in the ceramics industry to portion up clay for pot making and to cut thrown pots from the wheel.
Wirecut bricks have thousands of variations in both colour and texture. Usually they produce the cheapest brick facings available as the manufacturing process is highly automated.
Stock Bricks
The clay has water added so that it becomes what is referred to as a “soft mud”, and then moulded into the desired brick shape, before being allowed to dry prior to firing in the kiln.
Much of this brick making process is automated. The finished bricks tend to be slightly irregular in shape. The stock bricks are usually a little more expensive than wirecut bricks.
Handmade Bricks
Handmade bricks are usually made in moulds on a bench, in almost the same way as a stock brick. Because the clay isn’t firmly compacted into the mould by a machine, each brick normally has a distinctive creasing pattern on the faces that are known in the brick trade as a ‘smile’. Handmade bricks are a very desirable product and have the most expensive and intricate facings. Handmade bricks are considered to be well worth the cost on prestige building projects.
Fletton Bricks
Fletton bricks are also known as ‘London Bricks’, some may even refer to them as LBC (London Brick Company) bricks. Fletton bricks are a unique facing brick manufactured from the Lower Oxford clay that is found only in the South East of England. This clay contains coal traces, which burn during firing, which reduces the amount of fuel needed for the kiln. As coal is already present in the clay used in Fletton bricks the cost of firing them is reduced and the coal ingredients also produce some rather interesting effects in the finished bricks themselves.
Common Bricks
A cheap filler brick that is just plain and useful rather than being attractive. That said, some common bricks can have a charm all their own and are perfectly acceptable for some smaller jobs.
Engineering Bricks
The engineering brick really is the workhorse of the brick family. These bricks are tough, strong, hardwearing but not usually very attractive to look at. They are particularly resistant to frost and water, making them ideal for groundworks, sewer works and retaining walls. These bricks can be quite expensive, but then they can be used for pretty much anything.
Concrete or Calcium Silicate Bricks
These type of bricks are popular in areas where quality brick making clay is rather scarce. Some of these bricks are of very poor quality, but some may be split-faced or have a pitched face in an attempt to give the consumer the impression that they are buying something more than just plain and boring concrete. These bricks are pretty cheap and cheerful and you could use them for areas that you are unlikely to see.
Reclaimed Bricks
These bricks are also referred to as salvaged bricks. These are bricks that have been rescued from old buildings and usually have the majority of mortar cleaned from their faces. It is important to buy theses bricks through a reputable merchant, if not you really have to know what you’re looking for to make sure you get a good quality brick. Many people buy these bricks because of their charm. It is also possible for consumers to get hold of bricks from a particular building that held fond memories for them, such as a retired police officer being able to build his garden pond with the yellow reclaimed bricks from his old station.
There can be a high level of wastage in reclaimed bricks. Many of these bricks will be the old Imperial sizes which are incompatible with the modern metric bricks. Also a lot of people assume that as the bricks have been reclaimed from a demolished building, they will be cheap, this is not the case! Cleaning up and sorting reclaimed bricks is a very labour intensive task and the bricks can sometimes cost twice the price of a quality facing or a ‘reproduction’ reclaimed brick.
Special Bricks
Special bricks are effectively any brick that isn’t a rectangle. Confusingly, there are “standard special bricks”, such as bullnoses, cants and radials, and even “special special bricks” such as cills and quoins. These special bricks allow some amazing design possibilities and make brickwork the most aesthetically pleasing medium for building.