Evaluation of environmental comfort and energetic performance in school buildings. Research contribution to analysis and intervention choices. The research experience regarding schools in the “City of Rome” Guideline definition for interventions on existing buildings

Assumption It is well known by now, how the high energy costs and pollution related problems, which on larger scale cause considerable environmental damage, have led to the priority of designing energetically virtuous buildings in order to reduce or - where possible – abolish the use of fossil fuel. In the Italian context, however, we are facing a huge patrimony of existing buildings, whose energetic performance is often lamentable, but the buildings are not obsolete enough to deserve demolition and to be substituted by new construction of higher energetic efficiency. It is therefore a must for us, to identify project strategies which will allow us to intervene in an efficacious and conscious way on existing buildings, such as to bring them to a level of efficiency comparable to the one we would consider prerequisite for new constructions. The only way to obtain true energetic efficiency is to involve the entire building, and this is why we are convinced that – in order to reach the goal of bio-climatic building renovation design - it is essential to deeply investigate the characteristics of the building we are to intervene on, by monitoring its energetic behaviour and by simulating the most possible reliable mathematics models in order to evaluate the renovation intervention envisioned. Analysis The case study chosen is a nursery in the cityof Rome, built in heavy prefab. The primary goal of this research is to identify corrective strategies of intervention on the building, in order to guarantee comfort to the users, in winter as well as in summertime. At the same time we had to reduce energy bill amounts as well as of CO2 emission. Our first step was a profound analysis of the building itself. We made a thermographic survey in static and transitory regime of the entire building envelope, in order to identify its weaknesses; then we measured the thermal resistance of all external components. The obtained data have then been used as input for the calibration of mathematical simulation models . Working on an existing building has allowed us to compare our model expectations with the real data obtained by observation of the building. At the same time, we realized a data survey campaign (air temperature and humidity, internal and external building envelope temperature, natural illumination and CO2 concentration) from autumn until summer holidays, with the purpose of verifying comfort levels. Conclusions The analysis of the existing building and the evaluations obtained through calibrated simulation models allowed the research group to identify the necessary interventions for a master plan to be accomplished. As a subsequent step, a new monitoring will be performed in order to verify the efficacy of the renovating intervention.