Original Article Journal of Building Physics 2017, Vol. 40(4) 372–395 Ó The Author(s) 2016 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1744259116673368 journals.sagepub.com/home/jen Performance comparison between an improved and a classical Trombe wall: An experimental study Narjes Dimassi and Leila Dehmani Abstract In this article, the comparison of energy performance between a classical and an improved Trombe wall of a model test room has been carried out experimentally. The case study is conducted in Borj Cedria, Tunisia, where there is always heating require- ments. Here, we propose an improved Trombe wall whose absorber wall is covered with a thin black copper panel backed rather than simply painted black wall. The pro- posed idea would offer improved thermal performance, especially in natural convection. The comparison shows that the improved Trombe wall design gives an increase for both conductive and convective flux. The results show that the improved Trombe wall works more effectively than the classical Trombe wall system in utilizing solar energy for the example of test room. Keywords Solar wall, modified Trombe wall, passive solar heating, classical Trombe wall Introduction At present, the building sector in Tunisia is the largest energy consumer, mainly used for heating and cooling, and it is expected to be the first energy consumer by 2020 (Agence Nationale pour la Maitrise de l’Energie (ANME), 2004). Therefore, Laboratory of Wind Energy Management and Waste Energy Recovery (LMEEVED), Research and Technology Center of Energy, Hammam-Lif, Tunisia Corresponding author: Narjes Dimassi, Laboratory of Wind Energy Management and Waste Energy Recovery (LMEEVED), Research and Technology Center of Energy, B.P. 95, Hammam-Lif 2050, Tunisia. Email: dimassinarjes@yaoo.fr