The molar volume is an extensive property that can be given by the pressure derivative of the Gibbs energy of a phase. Therefore, supplementary terms can be added to the Gibbs excess energy model of a phase in order to reproduce, and eventually predict, volumetric properties. Those terms take in account the pressure variation of the Gibbs energy, and the variation can be related to the composition of the system ans/or to its temperature. Molar volumes and expensivities as function of temperature have been obtained for 13 elements, including aluminium and its alloying elements (Mg, Si, Cu, Zn, etc.) by making a critical evaluation of the data available in the literature. Excess volumes of binary liquids have been optimized by adding pressure dependant terms to the excess Gibbs energy functions. The further step in the work is to extend the model to ternary and multicomponent systems.