The environmental sustainability assessment of building materials is a well known critical issue. The theoretical and technical difficulties were shown by several researches started in the nineties and sometime still ongoing. Most of the researches were (or are) addressed to develop indicators in order to provide ecological information about materials but only few outcomes can be assumed as really considerable for an environmental assessment. Such difficulties are particularly relevant for those tools addressed at helping architects to select sustainable options during the design stage. Two European directives recently issued become the opportunity to overtake such impasse. The former, aimed at carrying out building product’s data sheet concerning the energy and environmental performances of product itself. The latter, aimed at developing a methodological approach including the calculation of the primary energy needs due to production stage of building materials.