Traditionally, West African villagers build their roofs with timber frames. In recent years, significant demographic growth and the retreat of the forest have led them to turn to the purchase of sheeting and squared rafters to build their roofs. A rather disastrous solution: these materials must be imported and are therefore very expensive for the future owners; besides, they offer poor thermal and acoustic insulation, not to speak of aesthetics.
To improve this situation, Thomas Granier, a masonry contractor and a native of Ganges, in the Hérault, formed the idea of importing an ancestral technique to the Sahel, known by the populations of the Upper Nile (southern Sudan and Ethiopia). The Nubian Vault technique only uses raw earth as a raw material, but demands specific apprenticeship and knowhow: the production of mortar and sun dried bricks.