Alongside active energy improvements dealing with energy supply systems and building devices and services, passive techniques targeting enhancing the building envelope are demonstrated as viable options to improve the overall building performance. In this study, a holistic investigation of integrating phase change materials within the building envelope is presented aiming to improve indoor thermal comfort and reduce energy consumption. Thus, dynamic energy modeling and performance evaluation of building envelope enhanced with phase change materials under Danish conditions is carried out. A standard Danish office is considered as a case study where a systematic screening of 17 PCMs is performed to select the optimal PCM based on EnergyPlus dynamic energy simulations. A PCM with a melting temperature of 24 ∘C, a crystallization temperature of 21 ∘C, and a latent heat of fusion of 219 kJ/kg was identified. In addition, a parametric analysis is carried out to evaluate the impact of the PCM thickness and location within the building envelope on the energy performance and the indoor thermal comfort. It was shown that using a 40 mm PCM layer placed on the interior side of the building components provide the best scenario. Based on the results of the parametric analysis, the implementation of the optimal PCM to enhance the building envelope of four case study buildings is carried out. This includes a standard one-story single-family house, two-story house, apartment building and an office building. Nevertheless, a sensitivity analysis is performed to assess the effect of various factors on the PCM selection under Danish conditions. It is shown that the building insulation level, room cooling and heating set-points, as well as the ambient weather conditions have a large impact on identifying the best performing PCM for Danish buildings.