Making bricks – a brief history

Brick is one of the oldest building materials and its story starts at the very beginning of civilisation. The mud brick was invented between 10,000 and 800 BC; the moulded brick was developed later, in Mesopotamia about 5000 BC; but the most significant landmark was the invention of the fired brick in about 3,500 BC.

It was this that enabled the construction of permanent structures in areas where it had not been previously possible. Firing the brick gave it the resilience of stone but with the added advantages that it could be more easily shaped and provide potentially endless repetitions of decorative patterns. Building with bricks that are dried in the sun is one of the oldest and cheapest methods of building construction. It requires very little in the way of technology and the raw materials are generally available on site, making it a very sustainable construction technique. Making mud bricks conserves natural resources and reduces long-term costs for Habitat for Humanity homeowners.

The uniformity of the brick is one of its most important properties and is traditionally achieved by making them in moulds. The most common type, the open mould, is simply a box without a top or bottom. Another alternative, the box mould, is similar, but has a bottom.

The Quick Guide to Brick Making
Habitat for Humanity Bricks

The Quick Guide to Brick Making

A woman in Orange Farm, South Africa, prepares soil to make more bricks while others dry out in the sun behind her.

Soil heavy in clay content is ideal for use in brick building because clay is the element that makes the bricks hard after baking. In some regions of the Democratic Republic of Congo, the soil found in termite "hills" is preferred as the termites build their mounds by bringing up clay-rich soils from beneath the surface and secrete a natural bonding substance in their saliva during the process.

The soil is mixed with dried straw and then put in a brick press. Once out of the press the raw bricks are set out in the sun to dry. You can see in the picture how the bricks are stacked, allowing air to pass in between them in the drying process. Bricks that are baked in the sun need to be kept damp to slow the drying process so that they do not crack.

Bricks that are baked have another step in the process. Upon drying, the bricks are baked in a brick oven (these ovens are almost always constructed by the brick makers themselves) – it is at this stage that the bricks become really hard and properly water resistant. The spaces in between the bricks are covered by mud to reduce the amount of heat that escapes the brick oven.

Once the fire is lit in the oven, metal plates are placed in front of the openings to contain the heat. When the fire cools, the bricks are ready for use in the construction of homes – in some areas, where cement is expensive or hard to get hold of, the mortar mixture can be made with locally available chalk.

Habitat for Humanity Bricks

A freshly pressed brick in Sri Lanka.

Because Habitat for Humanity works in 98 countries around the world, the bricks used in the construction of homes vary hugely. In many Asian countries such as Thailand, many communities use an interlocking brick.

This design makes house construction quick and easy for even unskilled builders – they merely slide the blocks down steel supporting poles that run through the centre of the brick and then pour in a cement-like material that acts as the mortar … easy!

In parts of Africa and South America, homeowners make their own bricks using local materials. In the case of Democratic Republic of Congo, they make what could be loosely termed as an "organic" brick from termite mounds to save on costs!

Residents of Orange Farm in South Africa have even used their brick making machines to generate income for more houses in the community – using brick making machines supplied by Habitat for Humanity, they have setup a small co-operative that produces and sells bricks. The outcome is a volunteer workforce, producing good bricks that go on to pay for more people to leave behind a life of poverty.

Making bricks at building centres is also helping communities ravaged by the tsunami to generate an income. Many of the worst affected were fishermen, who lost their homes and livelihoods when their boats were dashed to pieces. Habitat is paying workers to manufacture bricks at the building centres, which means more bricks for house-building and an income to start people in great need on the road to recovery.

The houses we are building for tsunami survivors in Indonesia are designed to provide a high degree of protection from earthquakes. They are made with fired brick and reinforced concrete posts and beams.

Earthquakes are common in Guatemala as well, so local experts have designed Habitat for Humanity houses to resist tremors. The houses are made of hollow concrete blocks with steel rods to reinforce the walls every metre. Horizontal rods run through U-blocks at the foundation, window sill and top, and the spaces around the rods are filled with concrete. So, the simple brick can be innovatively used to produce homes that are environmentally appropriate and cost effective.