Abstract: Provided herein are form stabilized phase change materials and methods of their manufacture. Form stabilized phase change material compositions comprise porous particulate carriers impregnated with at least one phase change material. The particulate carriers are of a specific size range depending on the density and loading capacity of the particles. Exemplary carriers include expanded perlite with a particle size of greater than approximately 0.5 millimeters. In some examples, the products may have phase change material at 40% or more of the final composition by volume. Additionally, methods of manufacturing the form stabilized phase change materials are provided, and exemplary building materials and shipping containers are provided.