Technology offers alternative cheap housing

By Pocyline Karani

The young man grips the lever and arches his body sharply down. The machine clanks. Inside its chamber a new brick is pressed – a stabilised soil block (SSB), a mix of water and soil with a fraction of cement.

This and other simple building technologies now have the potential to transform lives in Kenya’s highly populated cities.

Some of these technologies originate from India, but holds the potential to provide alternative and affordable houses in Kenya. With such simple technologies using soil and little cement to make bricks, researchers from University of Nairobi confirm that the end product is strong enough to build a four storey house.

Non Governmental Organisations support this new technology say it would lower the cost of building a self-contained house by 42 per cent.

For instance, a modern two-bedroom house in Nairobi may cost Sh2.3 million, but it could cost as low as Sh966,000 using this new technology.

A tenth of Kenya’s population, which is about three million people live in the cities

Most of them live in unrecognised informal settlements or in cheap rentals. Social conditions are poor, services non-existent.

One house built every day

Appropriate technologies could help people living in informal settlements build affordable houses. According to ITDG, SSBs cost one penny each. But until recently people did not take them up because the houses would not be legally recognised.

This is because the current housing standards have been defined by the colonial authorities so as to protect areas regarded as ‘good’ neighbourhood against settlement by poor.

A campaign steered by ITDG and its partners had this changed 10 years ago. It was replaced with a national housing code, which accomodated low-income people. More institutions have moved in to introduce new construction technologies. In 2005, an America company, Wall-Ties & Forms (WTF) Inc, introduced a new construction technology with a system that allows completion of at lest one full house every day.

With this technology using aluminum concrete forming system, a small crew of workers is able to cast the entire interior and exterior walls of an average sized family house in just one day.

With the crew working 350 days a year, they will produce 350 new houses in one year. A cluster of 10 crew means they will produce 3,500 all concrete houses annually.

The WTF concrete forming system is a series of lightweight aluminum panels that are custom-built based on the architectural design of a house. This technology is cheap and has been effective in Mexico.

Other technologies regarded as cheaper and designed to speed up construction of buildings have been approved locally. With technologies such as Moladi that takes a month to complete a house could cut building cost from Sh3.5 million to Sh1.45 million. This technology was used to construct prison warden houses in Langata and has proved effective for mass production at a lower cost.

Stakeholders are soon looking into developing low cost housing units that would go for as little as Sh600,000.