Energy and environmental assessment of heritage building retrofit

In the transition to a low-energy economy, the building stock renovation should address the reduction of the environmental impacts, by means of suitable energy retrofits oriented to meet current energy efficiency regulations, construction guidelines, and standards on comfort and operation. With regard to the historic segment of the building stock, suitable refurbishment policies are needed to avoid the loss of their heritage values, even if this is a complex issue requiring interdisciplinary approaches, dedicated diagnostic procedures, and specific tools. In this paper a suitable method for energy and environmental assessment specifically devoted to historical building retrofit, following a life-cycle approach, is proposed. The method allows to assess the energy saving for building operation arisen from the retrofit actions, the increase of the embodied energy and the environmental impacts within the building life-cycle, and to understand whether the achieved energy benefits could be supported in a life-cycle perspective or were overcome by the environmental burdens of the actions. This method could be used to support public policies that would encourage the preservation of cultural value buildings, allowing for the assessment of the most effective actions addressed to save energy and to minimize environmental impacts along the whole building life-cycle.