The case study refers to a project being implemented at the headquarters of IIPLE, Institute for the Professional Education of Construction Workers of the Province of Bologna. The intervention involves the construction of a metal structure mezzanine inside the existing building to create two new classrooms. The mezzanine, with a surface area of approximately 160 m2, will be built within a portion of the existing double-volume prefabricated space used for laboratory activities. The dividing walls of the classrooms will be made using sound-absorbing plasterboard, as will the flooring and ceilings. A dedicated air conditioning system will be installed, located inside the false ceiling of the new rooms on the first floor. The existing non-performing fixed windows in the two bays corresponding to the new classrooms were replaced with operable thermally insulating windows. The project involves mandatory excavation works up to a depth of -1.50 m from the finished floor level for the construction of the foundation plinth. Excavation sections are also planned for connecting the beams between foundation plinths and perimeter walls. The masonry works envisaged are all of the dry construction type, with variable stratigraphy depending on the location and the performance required. Different typologies are defined in the project plans. In addition to the screed, the project includes lightweight screeds for the passage of utilities. The internal divisions were created using dry construction systems, in particular plasterboard panels with high fire prevention and acoustic insulation properties. Dry systems have been tested, guaranteeing their biocompatibility and environmental sustainability. The tests conducted on the materials include assessments relating to emissions of harmful substances, heavy metals, radioactivity, fine dust emissions, diffusion and absorption capacity, heat behavior and pollution. More information