Low energy buildings. How can they be easily evaluated?

The conciliation attempts to preserve the urban cultural heritage with the cities development and their centre renewal, leads to the conservation, restoration and rehabilitation of the old buildings in order to make them adequate to the modem life-style. The protection and enhancement of cultural heritage with low energy technologies in building restoration, naturally requires from the urban planners, or more specifically, from the architects, the knowledge of thermal design tools that permit them, in a simple manner, to evaluate the efficiency of their solutions. So, the aim of this paper is to provide a simplified method of evaluating hourly indoor air temperatures of free floating buildings, as a function of the external climatic conditions and of the envelope. In a primary stage of the project, the planners can test different architectural solutions in order to determine which one leads to the best thermal performance of the building, i.e., which one leads to the lowest energy consumption. The design tools available are very complex and need specialised technician to implement them in high capacity computers. The methodology presented in this work is a simple one, but at the same time very accurate, and was implemented in a very user-friendly computer program that is fast, easy and efficient to use.