The learning in architecture has a complexity that is a field that must be synthetize aesthetics and functionality. Somehow students are not very effective when they try to mix this terms, in most of the physical topics. To reach this there is a subject “ Applied Physics to Structures “ that shows development of a unification process for learning, crucial to energetic parameters where Energy is the most fundamental parameter for all processes. After the theoretical explanation, a practical application of this knowlodge is propose to existing buildings with a method that is applicable to rehabilitation and allows the study of structural elements without any kind of intervention, as show in the examples of this study as la Sagrada Familia, the Gotic Cathedral ofLeon and an application to the cathedral of Vitoria and other buildings.