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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License
Lorenzo Leoncini1 and Edoardo Cappelli2
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DOI:10.17265/1934-7359/2025.10.002
1. KEP Energy, Florence 50133, Italy
2. University of Florence, Florence 50139, Italy
This study analyzes the energy impact of applying green roofs on flat roofs of existing buildings, assessing their potential to reduce the demand for non-renewable primary energy for heating and cooling. Through dynamic numerical simulations conducted on two real buildings located near Florence, Italy, and modeled in 130 different European locations, with a particular focus on the Mediterranean climate, it was possible to quantify the energy benefits derived from the application of green roofs on existing structures. The results show that, while the effect on heating is limited, with an average reduction in energy demand of only a few percentage points, the impact on cooling is significantly more pronounced, with average savings of 20% in non-renewable primary energy, particularly in Mediterranean climates with high CDD (cooling degree days) values. The study confirms that green roofs can be an effective solution to improve the energy efficiency of existing buildings with flat roofs in the Mediterranean climate, in line with European goals for reducing CO₂ emissions and promoting renewable energy.
Green roof, flat roofs, renovation, energy efficiency, numerical simulation, Mediterranean climate, energy savings, summer cooling.
Journal of Civil Engineering and Architecture 19 (2025) 470-477
doi: 10.17265/1934-7359/2025.10.002
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