This paper draws the attention of the structural designers and architects to the importance of employing the environmental data in all design and construction stages of buildings. The paper dispelled the fact that final design of buildings cannot be performed ignoring the environmental data, especially in the hot-dry tropical regions. In that respect, the paper focused on the introduction of the solar radiation values that are received by the buildings during the day into the selection of most suitable construction material, as well as the design of thermal insulation thickness for walls and roofs of buildings at Khartoum State in Sudan. The paper assumed the walls and roof are the media of heat exchange between the internal space and the climate, excluding the building floors. The traditional heat transfer equations were used for estimating the main values of thermal conductivity at the level of the building and not the region. The paper also minded the financial situation of the owners and assumed three thermal levels for a building in the study area at Khartoum State. Inside and outside temperature measurements on a study building, which is insulted using thermal level three, are presented. The results showed that the thermal design of concrete sections qualifies it for operation with high efficiency by reducing the primary and secondary loads. Moreover, it raises the lifetime of the building and avoids the phenomenon of creep. On the other hand, the paper concluded that: reduction in the solar radiation by 20% to 40% will reduce the building thermal operational cost by same percentage. Also the paper puts preliminary steps towards establishing measures to assess the thermal performance of any building according to: Thermal conductivity, solar radiation and latitude. Emphases for interaction and integration of the role of architect, civil, material, and air-conditioning engineers must start in the early stages of building projects specially at the hot-dry regions.
