The green roofs, ideal against summer heat, have proved to be highly performing even in the case of extreme weather events typical of the winter seasons. A recent research, carried out by the Enea Casaccia Research Center, underlined it. According to the study, "green coats" not only absorb up to 50% of rainwater by regulating its flow into the city's water system, but also generate natural ventilation along the external surface of buildings. Result: maximum moisture mitigation caused by rain. "In winter - explained Carlo Alberto Campiotti of the Energy Efficiency Unit Department of ENEA - plant coverings improve the thermal insulation of the top floors of buildings and contribute to reduce the danger of extreme weather events, such as heavy downpours and torrential rains falling increasingly on the cities because of the climate changes now happening in the Mediterranean area". A short step from theory to practice at the ENEA Casaccia Center: an experimental vegetation cover was created on the roof of the "School of Energies", consisting of a soil thickness of only 20 cm, made by plants resistant to the aridity of the roof and at the same time to the cold weather. "This extensive plant covering - specified by ENEA - does not exceed 100 kg per square meter, but when it is irrigated, or in case of rain, it can weigh up to 6 times because, like a sponge, it holds water for 2-4 hours before draining it along the descendants of the building. And this is one of the reasons why, during the design phase of a green roof, it is essential that a technician also performs the static calculation of the building". For these important added values, the "green roof" can have a significant impact on the urban microclimate during all the months of the year, helping to reduce consumption related to heating and cooling. "Considering that heating and cooling a house can impact the 40% of energy consumption - says Roberto Rescia, CEO of CoverHat - with very bad consequences for the health of the environment, we believe that “green plant coverings” could be a technology to be developed on our products, not only for its high sustainable value, but also for its performance. A perfect circle that preserves habitats and people, also contributing significantly to the aesthetics of cities".