This abstract is part of the in progress PhD research entitled “Definition of a methodology for energetic certification in residential field after energetic efficiency decrees in Construction” fullfilled for the Doctoral course of “Redevelopment and recovery of urban buildings” of the Faculty of Architecture “Valle Giulia”, University of the Study of Rome “La Sapienza”, with the collaboration of the Research Centre of Casaccia, E.N.E.A. Energetic certification is likely to be at risk of remaining nothing else but intellectual practice. It’s a fundamental question for the energetic certification system to introduce suitable technical solutions to improve buildings energetic performance and make the real estate market aware of it. Albeit it might be insufficient because the practices results, that are both energy and money savings, are required to be transparent and easy to read from final users. In this specific way, the energetic certificate proves to play the leading role in the whole process as official recognized tool, otherwise the procedural diversification, both on a large and on a small scale, can compromise the tool effectiveness. Keywords of this paper: energetic certification, existing buildings, available methodologies, calculation praxis, simplification, buildings energetic performance, diffusion process, citizens’ needs, program targets, technical problems.