[ABSTRACT The phase change materials, known as PCM (due to short for Phase Change Materials) are materials with a high latent heat during phase change (liquidsolid) store or release large amounts of energy. The interesting thing about these materials is that, during phase change, its temperature remains constant while the material is by absorbing or releasing energy. The objective of this project is to study how adding different influences PCM in gypsum to assess differences in their properties, both physical and mechanical and thermal. In the first place is a small introduction of PCM materials and their behavior, naming the classification according to their origin and heat storage capacity. This project will build on the PCM that are most widely used in construction, which are of organic origin based paraffins as they have good durability, chemical stability and non-toxicity. The experimental phase begins doing a study of different formulations to achieve the suitability of pasta, then held specimens of different sizes to perform the different tests mechanical, thermal and microscopic. After completing the tests and the results obtained, we proceed to interpretation. In conclusion we can say that the addition of PCM significantly improves the thermal properties of the material but do decrease the mechanical properties thereof shall not be important because the study is done with a purpose of coating material and not structural