The research is focused on the concept of ‘utility’ regarding the sustainable building assessment methods. The study presented is part of a wider research that analyses the sus-tainable building assessment methods regarding the challenge of sustainability. Keeping in mind that the condition of sustainability is the material cycles closure, we highlight the place that ‘utility’ occupies in the measure of the sustainability. We explore how the standards of LCA and sustainable building assessment deal with this question. Then we point out the impossibility of an objective measurement of utility and the fact that the methodologies adopt a conventional definition of this concept. Finally we contribute a formulation that has to allow us, in future works, analyzing the definition of utility adopted by the different methodologies and the corresponding implicit judgment values.