regulators must guarantee the highest efficiency in the consumption of water; _ energy and atmosphere: making best use of energy from renewable and local sources, it is possible to reduce significantly the energy bill of the buildings; environmental performance co r po r at e su st a in a b il it y pe r fo r m a n ce i n d ic at o r s a ss u r a n c e st at em en t _ quality of the interiors: the interiors spaces of the building must be designed to consent an energy balance close to zero and provide the maximum comfort to final users; _ planning and innovation: use of construction technol- ogies that improve current best practice is an element of added value, for the purposes of LEED certification; _ materials and resources: in the LEED assessment, build- ings using natural, renewable and local materials are given a higher score.