An ancient architectural technique, traditionally used in Sudan and central Asia, but until now unknown in West Africa, can provide the answer to the current problems of house-building in the Sahel. This technique - “la Voute Nubienne” or VN - makes it possible to build houses with vaulted roofs (on top of which a traditional flat roof terrace can be constructed) using basic, readily available local materials and simple, easily learnt, procedures.

What’s so special about the VN technique?
 the only raw material used is earth, for making both mortar, and mud bricks dried in the sun
 timber shuttering is not required to support the vault during construction
 the traditional methods have been simplified, and adapted to provide protection during the short but heavy rainy seasons of sub-Saharan Africa.

The major cost element in using the VN method is labour, thus keeping cash in the local economy; the raw materials are locally available and ecologically sound.

The VN technique provides people with a feasible alternative to building with imported sheet roofing materials and timber. It is essential that the technique becomes more widely adopted, and this is the declared aim of the “Voute Vubienne” association, through its programme Earth roofs in the Sahel .

The VN technique has been adapted to match the prevalent customs and traditional ways of imparting skills, especially in rural communities. The result is a streamlined technique, easy both to put into practice and to teach by example.

Most VN buildings to date are in rural areas, but the VN technique can be used in denser urban and peri-urban zones. The additional expense of transport of bricks and water to urban sites, and higher labour costs, may be counter-balanced by lower material costs, especially for two-storey buildings, when a VN vault can replace a costly reinforced concrete structure.

 Click on the drawings below to enlarge them