This paper reports experimental results on the thermal performance of fly ash-based 
geopolymeric mortars containing different percentages of phase change materials 
(PCMs). These materials have a twofold eco-efficient positive impact. On one hand, 
the geopolymeric mortar is based on industrial waste material. And on the other 
hand, the mortars with PCM have the capacity to enhance the thermal performance 
of the buildings. Several geopolymeric mortars with different PCM percentages 
(10%, 20%, 30%) were studied for thermal conductivity and thermal energy storage