Among the research activities that aim at reducing energy consumption in buildings and their impact on the environment is an experimental set-up that has several house-shaped cubicles constructed in Puigverd de Lleida (Spain). Assessing the environmental impact through studying the manufacturing, operational and disposal phases of these cubicles have been done in previous research. The objective of this paper is to investigate the use of esters as PCM in order to estimate its environmental impact in building envelopes in comparison to the use of paraffin or salt hydrates through a theoretical study. The evaluation of the environmental impact of this type of PCM material is conducted using Life Cycle Assessment (LCA) based on the Eco-indicator 99 method. It is found that the impact of ester used as PCM presents slightly better results than the case of using salt hydrates during the manufacturing impact. On the other hand, the use of salt hydrates or ester as PCM in the cubicles results in an impact reduction of 9% and 10.5% respectively, compared to the case of using paraffin. (C) 2012 Elsevier Ltd. All rights reserved.