Abstract This study aims to develop new environmentally friendly construction materials that compete with modern materials in civil engineering. The paper deals in particular with tropical clays in order to develop new processing of clay based construction materials such as bricks, roof and floor tiles, for building needs in developing countries. Physical and thermo-mechanical characterisations are carried out on six tropical clay varieties from Togo (West Africa). The mechanical resistance is carried out on clay structures fired at 500 °C, 850 °C and 1060 °C. Relationships between the physical properties and the mechanical characteristics of clay structures have been established.