Monitoring and certification activities of the energy and environmental performance of green residential buildings

The evaluation of the overall performance of a green building is complex, since many energy and environmental aspects have to be considered. The Umbria Region in Italy, through various public tenders, has recently funded several residential buildings, innovative in terms of construction quality: green technolo-gies and sustainable solutions, such as natural building materials, integrated sunspaces, PV modules and solar collectors, geothermal heat pumps, had to be adopted to obtain the public contribution. The paper presents the study carried out on a green residential building, as an ex-ample of successful practice, with integrated solutions. It has a particularly well insulat-ed envelope (opaque and transparent materials), a geothermal plant with heat pump and passive solar systems. The benefits were evaluated thanks to the monitoring activity carried out by the University of Perugia, in order to verify the actual achievement of design objectives, to certify the real savings in terms of energy and environmental loads and to assess the indoor comfort conditions for occupants. In situ measurements (thermal, acoustical and lighting performance) were carried out for a long period. Energy simulations were performed using a simulation code which implements the algorithms required by the Italian law. Moreover, a comparison between real consumption and estimated energy requirements obtained through the simulations was carried out. Finally, the data derived from simulations, monitoring activities and technical doc-umentation were used to characterize the building from the environmental sustainability point of view. The method of the Certification of Environmental Sustainability by Um-bria Region was used. It was borrowed from ITACA procedure (an Italian procedure similar to LEED) and consists of 22 worksheets, one for each different performance in-dicator, at the aim of carefully describing the environmental quality of the building