||The present work aims to study an application of the composites of husks of rice in building. This study consisted in formulating a set of composites of husks of rice experimentally. Comparing with dosage made of cement usually adopted for the blocks for flooring in Benin and in Togo, a deduction of optimal formulation of composite of these blocks is proposed from the worked out formulations. For the composite obtained, a study of the thermal conductivity has been worked out. Some blocks for flooring have been manufactured and have been tested in simple compressive stress. The physical and mechanical properties of the blocks for flooring made with husks of rice have been compared to those of the blocks for flooring made of sand and cement. Optimal resistance to compression of the blocks increases with the proportion of cement on the mixture cement and husks of rice. In addition, the coefficient of thermal conductivity of the composite cement-sand-husks of rice at relative humidity 8%, is quite low. Blocks for flooring in composite with rice husk are about 46 % lighter than those made of sand and cement. Proportion cement/rice husk is 1,02 (against a number generally upper to 2), corresponding to a specific gravity of 400 kg/m3. Proportion sand/rice husk is 40% .Although their cost is a little more important, although they present a risk of disintegration for Cement/Rice nearby unit, the decrease of permanent loads of the superstructure of buildings obtained by using composites with rice husk is originality. So, it's evident from this comparison that the use of the composite made with husks of rice will contribute to decrease the weight of hollow flooring-tiles, and to improve the capacity of the so-called composite to block the heat flow.