The concluding part of a series on how India can learn from Africa on how to go about low-cost housing.

The technique of building vaults and domes with mud bricks and without the use of shuttering to support the roof were originally introduced into Niger by the organisation Development Workshop in a training programme in 1980 at the invitation of ISAID, a Canadian NGO, at the time operating near Filingue, close to Niamey.

Impressed by the buildings that were constructed following the training programme, and by the degree to which the techniques of earth vaults and domes were taken up spontaneously by the local population, the IUCN/WWF decided to promote the same techniques in the Air and Tenere region, seeing that they were ideally suited to the desert climate and to the material resources available.

To launch the wood-less roofing programme in 1985, the project constructed its own headquarters building in Iferouane using the ‘new’ techniques.

This has been followed by a variety of other buildings, initially meeting direct project needs and increasingly finding ways of responding to public demand for construction using the same vault and dome techniques.

The techniques of vault and dome roofing that have been chosen originate in Nubia, upper Egypt, and the form of buildings using these techniques has become familiar to many, particularly through the work of architect Hassan Fathy.

But in the nine years of building in Niger with vaults and domes, the forms have evolved and acquired a more distinctive local style.

By adding these round-domed rooms to the original architectural vocabulary of rectangular spaces covered by vaults or domes, the buildings have also become structurally less complicated and easier for local builders to construct.

By removing the right-angle corner and the triangular corner support, which transfers the form of the roof from its rectangular base to the round form of the upper dome, the problems of good bonding and careful construction in the corners where the thrust is at its maximum are removed.

The builders appreciate the simplicity of this form and find that the time taken to construct a room is much less than that for a rectangular room covered with a vault or dome.

They also appreciate that the work of building the roof can continue straight on from the walls, using the same materials. Earlier, much time had to be spent in obtaining the wood and branches for the roof.

A cost comparison between a rectangular room, covered with wooden rafters, grass matting and earth, and a room with an earth dome shows that the cost of materials for the latter is almost a quarter of that of obtaining the wood and matting.

The practical process of disseminating the techniques to the local population has been three-fold.

The IUCN/WWF programme supported these activities through the full-time presence of a technical assistant, Peter Tunley, who was the main person behind the development of local building skills and providing help to local builders when they worked on smaller private houses.

Development Workshop provides additional backup support dealing with specific technical issues encountered by the project, including the production of a manual explaining the techniques.

The result of these activities over the past so many years is a growing number of skilled builders in the area who are able to construct vaults and domes without supervision.

I feel sad when I come across articles covering innovative construction techniques in foreign journals. In Bengal, the skills displayed by the masons impressed the colonial settlers. But they were essentially executors and had constructed what was told to them.

It is time we started experimenting with our own resources and available materials. There is no dearth of skill.

I am eagerly waiting for the day when I can proudly show off an article on experimental housing in a remote Bengal village published in an international design magazine.

The author is an architect and urban designer