Green roofs represent a valid alternative to traditional roofs and are now a solution adopted by many designers, both for reasons related to style but above all with regard to improving the performance of buildings. They are linked to the Smart Cities theme, which encompasses concepts related to a new way of looking at urban reality, focused on citizens' well-being and energy efficiency. Green roofs are permeable spaces capable of combating pollution and fostering countless benefits for the environment, contributing to energy savings that in some cases amount to 10% compared to a building with a traditional roofing system.

These gardens, located on the tops of a wide variety of building types, are divided into two types: extensive or intensive depending on the thickness of the substrate. The extensive green roof is suitable for thin layers, is generally not usable and requires little maintenance throughout the year. Intensive, on the other hand, is the more traditional solution and allows for a wide variety of plants, shrubs and trees thanks to a thicker stratigraphy.