The Retrofit of Existing Buildings Through the Exploitation of the Green Roofs–A Simulation Study

Green roofs have several environmental benefits, such as improving building energy efficiency. As the existing Italy building stock was built before any roof insulation was required, the existing buildings will benefit most by the green roofs. The exploitation of a green roof for retrofitting of an existing house-holiday placed in the south part of Sicily was studied. The building energy performance and the dynamic thermal behavior of the green roof has been evaluated using a transient simulation program. The results of this study indicate a remarkable reduction both of the cooling and heating load respectively of about 80% and 34%. Dynamic simulations have proven essential that the typology of green roof investigated delays and attenuates the outdoor heat wave better of traditional roof diminishing the average daily temperature fluctuations. Therefore, the green roof shows a strong potential for the retrofit of not well-insulated building in Mediterranean area