A CRITICAL APPROACH TO IMPROVE DAYLIGHT CONTRIBUTION AND TO CONTROL LIGHTINGS IN EXISTING BUILDINGS CASE STUDY: INPS OFFICE, SESTRI PONENTE

Most of existing buildings need retrofit interventions to reduce high energy consumption related to air-conditioning and heating and for lighting of confined spaces. Planning retrofit projects in existing buildings is more common than designing new constructions [1] and it is also incented by European policies which support the concept of Near Zero Energy Building [2]-[3]. This study focuses on interventions related to the correct management of inside lighting which is a very interesting topic, although its potential remains largely unexplored. This article documents a case study analyzed for a graduation thesis that was developed in the context of the long-lasting relationship between the DAD (Department of Architecture and Design) of the University of Genoa and the office of the INPS (National Social Insurance Agency) in Genoa. The subject matter of this research is the INPS office building in Sestri Ponente, Genoa. As the lighting system had to comply with the criteria of Conto Termico 2.0¹, it was proposed to modify the building to better take advantage of natural light. Thanks to the collaboration between the INPS and the DAD, it was possible to analyze a case study that represents a larger issue, related to artificial and natural lighting in existing buildings. Studying the relationship between architecture and lighting systems draws attention on problems that are often caused, on the one hand, by recurrent refunctionalization interventions involving a change of use and, on the other hand, by the building density of the context, which can considerably influence natural lighting. This last aspect is rarely taken into consideration at the planning stage. As a matter of fact, most times, for retrofit interventions, the issue of natural lighting is not considered as it should be, and when interventions are carried out to improve inside lighting, reference is made almost exclusively to artificial lighting. The case study did not focus on proposals for artificial lighting only, but it considered issues and potential of the whole building, which led to take into account hypothesis to use the existing natural light. The lighting calculation was done through the software Dialux Evo [4] which made it possible to build a reliable model. This allowed to focus on enhancing the existing lighting contributions, and to verify the possibility of channeling natural light.