History of the brick

History of the brick

Man has used brick for building purposes for thousands of years.  Archaeological excavations have unearthed a brick that authorities dated as 9,000 to 10,000 years old.  The oldest type of brick in the Western Hemisphere is the adobe brick.  Adobe bricks are made from adobe soil, comprised of clay, quartz and other minerals.  Adobe soil can be found in dry regions throughout the world, but most notably in Central America, Mexico and the southwestern United Sates.  The Pyramid of the Sun was built of adobe bricks by the Aztecs in the fifteenth.  Those bricks, made in areas with warm climates, were simply placed in the sunlight for hardening.  Sun-dried bricks, which were used extensively in ancient times, especially in Egypt, were made of clay mixed with straw.  Early in civilization, bricks were baked by using a fuel; these bricks were made of clay mixed with straw to give them added strength during drying and baking in crude ovens. 

Adobe brick near a construction site.  

Renewal of the surface coating of an adobe wall.  

The manufacturing process of brick

The initial step in producing brick is crushing and grinding the raw materials in a separator and a jaw crusher.  Next, the blend of ingredients desired for each particular batch is selected and filtered before being sent on to one of three brick shaping processes which include the process or extrusion, molding or pressing, the first of which is the most adaptable and thus the most common.  Once the bricks are formed and any subsequent procedures performed, they are dried to remove excess moisture that might otherwise cause cracking during the ensuing firing process.  next, they are fired in ovens and then cooled.  Finally, they are dehacked – automatically stacked, wrapped with steel bands and padded with plastic corner protectors.  The link below is a video which can show more clearly about manufacturing of brick.  

Characteristic of brick

Brick can be solid, hollow or architectural terra cotta.  Individual bricks may serve a structural function, a decorative function or both.  The standard-size brick manufactured in BS 3921 is 225X112.5X75mm and the actual dimension is 215X102.5X65mm.  Furthermore, the minimum compressive strength is 5N/mm² over gross sectional area.  The surface areas of a brick are the face, the cull, the side, the end and the beds.  

There are three types of brick :

a. Building Bricks. Also called common, hard, or kiln-run bricks, these brick are made from ordinary clays or shales and fired in kilns. They have no special scorings, markings, surface texture, or color. Building bricks are generally used for the backing courses in solid and cavity brick walls.

b. Face Bricks. Face bricks are used in the exposed face of a wall. They are high quality, durable bricks with a nice appearance.

c. Clinker Bricks. Clinker brick are bricks that are over-burned in the kiln. They are usually hard, durable, and irregular in shape.

d. Pressed Bricks. The dry-press process is used rather than kiln firing to make pressed bricks, which have regular smooth faces, sharp edges, and perfectly square corners. Pressed bricks are generally used as face bricks.

e. Glazed Bricks. These bricks normally have one surface coated with a white or other color of ceramic glazing. Glazed bricks are often used for walls in hospitals, dairies, laboratories, or other buildings that are frequently cleaned.

f. Fire Bricks. Fire bricks are made to withstand high temperatures. They are placed in fireplaces and boilers because of their resistance to crack or decompose. Fire bricks are generally larger than regular structural bricks.

g. Cored Bricks. Cored bricks are made with two rows of five holes extending through the brick to reduce the weight.

h. Sand-Lime Bricks. These bricks are made from a mixture of lime and fine sand. They are molded under mechanical pressure and hardened under steam pressure.

i. Wirecut Bricks. These clay is continuously extruded to a required size and shape and then cut into individual brick by means of wire. Usually the cheapest facing available as the manufacturing process is highly automated.

j. Stock Bricks. These clay is wetted to a so-call “solf mud” and then moulded to shape, before being allowed to dry prior to firing in the kiln, a bit more expensive than wirecuts brick.

k. Handmade Bricks. Usually made on bench, in a mould, much as described as a stock brick. These clay isn’t firmly compacted by machine, each brick normally has distinctive creasing known as a “smile”.

l. Fletton Bricks. This clay contain coal traces, which burn during firing, reducing the amount of fuel needed for the kiln, which is not keep down costs but also produces some interesting effect in the bricks themselves.

m. Engineering Bricks. Tough, strong, hard-wearing but not usually pretty. They have excellent resistance to frost and to water, making them ideal for groundworks, sewer works and retaining walls.

n. Concrete or  Calcium Silicate Bricks. Some are, quite frankly, bloody awful, but others may be spilt-faced or have a pitched face to give an impression of being something other than boring concrete.

Interesting fact of brick

Bricks are great insulators, they store hear energy from the sun during the day and release heat for several hours after the sun has set.  In hot climates, this thermal lag can translate into energy savings and increased comfort for the occupants.  Brick is known for its durability which can withstand severe wing and extreme weather conditions.  Furthermore, the natural color of a brick is determined by the mineral content of the clay used, the higher the temperature, the darker the brick.  The Great Wall of China, also constructed around 210 BCE, is made of 3,873,000,000 individual bricks.