A standard ultramarine pigment was used to produce phase change material composites. These type of pigments are conventionally used in construction sector once have been dispersed in different building components (paint, concrete, plastic). The main advantage of the use of n-hexadecane/pigment composite is that processes for building components manufacturing as the thermal storage capability is provided by the modified pigment. Vacuum impregnation method was employed optimizing the process variables to maximize the latent heat of the hexadecane/pigment composite. In addition to the process optimization, the stability of the composite having the maximum latent heat was investigated. The hexadecane/pigment composite providing the highest latent heat has a 20%wt. hexadecane adsorbed in the pigment. Durability of the material was tested by thermodiffractometic measurements showing a reduction of the area intensity up to 6.5% after the 100 cycles.