In a society with a high growth rate of comfort, the need to minimize the currently high energy consumption by taking advantage of renewable energy sources arises. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing for an increase in thermal comfort levels and a reduction of the use of heating, ventilation and air conditioning (HVAC) equipment, using only the energy supplied by the sun. Therefore, the application of phase change materials (PCM) comes as a possible solution in an attempt to solve, or at least minimize, the massive energetic consumption related to buildings. This research intends to understand the influence of microcapsules of phase change materials on mortars. The mortars studied in this work are mixed mortars of lime and gypsum. The proportion of PCM is 0%, 10%, 20% and 30%. In order to minimize some problems associated with cracking of the mortars, the incorporation of nylon fibers and superplasticizer was tested. A study of mechanical characteristics and some sensitivity tests to qualify the cracking of the fifteen compositions were carried out. It can be concluded that the use of PCM microcapsules in mixed mortars of lime and gypsum can be seen as a viable solution for applications in the construction industry once they present a compromise between their strength and aesthetic appearance.