In our national territory the rescue of the existing building property is a very important problem. For that reason, starting front the presupposition that the existing buildings, restoration finds its real achievement by means of technological and installing interventions strictly connected with the energy costs and consumptions, this study sets as a planning method on various degrees to analyze, single out and propose the possible solutions based on qualitative and quantitative researches into the thermo-physical behaviour of the above-mentioned buildings. From a research done into the principal building properties related with the different national areas we can single out significant morphological samples and typical technological structures. This first analytical study allows the singling out of significant building models on which it's possible to value the thermal behaviour and possible subsequent restoring interventions by applying computerized mathematical models or by operating diagrams deduced from them. First of all, these mathematical models for simulation allow a valuation of the main thermal parameters (dispersion both in absolute value and in volumetric factor, medium thermal transmittance (U value) of geometrical models deduced from the typical above - mentioned cases.