Life Cycle Analysis and Life Cycle Cost Analysis of green roofs in the Mediterranean climatic conditions.

The European policy as well as the national legislation framework set targets toward energy reduction and decarbonization in all sectors. Considering the building sector a number of regulations have been defined in order to ensure the energy as well as the environmental upgrade of the building stock. The paper’s main target is to evaluate from the environmental perspective the green roofs technology in Southern Europe. Therefore, a Life Cycle Assessment has been performed following the international standards of ISO 14040 series, supported by SimaPro Software. The aim is to define the proposed green roof system, analyze its environmental impact and evaluate the air pollutants levels related to the life cycle of its construction materials. A comprehensive review of similar roof applications is presented and results are compared with the ones regarding conventional roof typologies. The economic feasibility of the proposed roof types is assessed and evaluated based on a Life Cycle Cost Analysis. Thus, an integrated evaluation approach for the examined solutions is introduced, mainly focusing on Mediterranean climatic conditions. Moreover, a sensitivity analysis is conducted in order to define the impact of green roofs construction’s life span in terms of maintenance and renovation. As concerns the comparison of the suggested two roof types, and based on the sensitivity analysis the Traditional Horizontal Roof is proved to cause less environmental impact comparing to the Extensive Green Roof mainly because of the components use. Finally, the use of different insulation materials is examined and evaluated from an environmental point of view for the suggested typologies that are most suitable for the Mediterranean climatic conditions. More specific based on the sensitivity analysis’ results, and as far as global warming category, in both green technologies, levels have dropped by approximately 61% (from 2,13 to 1,52 kgCO2 and from 3,08 to 2,46 kgCO2, respectively) when recycled extruded polysterene is used in the construction stages for insulation. [ABSTRACT FROM AUTHOR]