This paper assesses the feasibility of impregnation/encasement of phase change materials (PCMs) in
lightweight aggregates (LWAs). An impregnation process was adopted to carry out the encasement study
of two different PCMs in four different LWAs. The leakage of the impregnated/encased PCMs was studied
when they were submitted to freeze/thawing and oven drying tests, separately. The results confirmed
that, the impregnation/encasement method is effective with respect to the large thermal energy storage
density, and can be suitable for applications were PCMs cannot be incorporated directly such as asphalt
road pavements.