Suitable thermal insulation solutions for Mediterranean climatic conditions: a case study for four Greek cities

The selection of thermal insulation solutions has to satisfy many criteria: energy performance is the obvious one, structural and safety performance is a prerequisite, and environmental and economic aspects are those that can make the difference. However, especially when buildings operate under the Mediterranean climates, where outdoor conditions have to be mitigated by the building fabric throughout the year, the contribution of an insulation solution to indoor thermal comfort is also an important issue. In this approach, an integrated decision support system was applied to assess thermal insulation practices used commonly in residential buildings in the Mediterranean area. The system assesses the buildings’ elements over their life cycle, with thermal comfort being evaluated by means of the PMV/PPD index. Twenty-three thermal insulation configurations were considered, with different locations (internal, middle, external), materials (expanded polystyrene, extruded polystyrene, stone wool), and thicknesses. As the results showed, the position and the thickness of the insulation materials have a large impact on the energy consumption, the overall environmental impact, and the life cycle cost of the building, while thermal comfort was affected to a lesser degree.