Thermal, economic, and environmental assessment of optimal aerogel insulation thickness compared with conventional...

The current study aims to optimize the use of insulation materials by determining the optimal thickness for exterior building walls across various Syrian climatic zones and different energy sources. The study focuses on a comparative analysis between nano-aerogel and conventional insulation materials, including Extruded Polystyrene (XPS), Polyurethane (PUR), and Glass Wool (GW), utilizing Heating and Cooling Degree-Days (HDD/CDD) methodology, to enhance energy efficiency in buildings. An integrated assessment was conducted through Life-Cycle Cost Analysis (LCC), encompassing thermal and environmental aspects, with a competitive advantage featuring the integration of space-saving requirements and the calculation of economic feasibility resulting from the rental of floor areas recovered through the use of low-thickness aerogel insulation. The results indicated that Glass Wool (GW) emerged as a highly feasible option prior to integrating space savings, with thicknesses ranging from 0.06 to 0.15 m. In contrast, aerogel achieved the highest efficiency when space savings were incorporated into the analysis, particularly in cities with high rental values such as Damascus, Aleppo (diesel fuel), and Latakia (diesel fuel), due to its remarkably low optimal thickness (0.001-0.011 m). Specifically, aerogel reached its peak efficiency in the city of Latakia (diesel fuel) at an exceptionally low optimal thickness of 0.001 m. At this level, the reduction in initial capital expenditure allowed space-saving revenues to dominate the economic balance, sharply decreasing the discounted payback period to just 1.2 years (the shortest value recorded in this study). This accelerated cost recovery pace enabled aerogel to outperform all studied conventional materials. The study concludes that there is a critical trade-off requiring a precise balance between the material's embodied energy and the sustainable economic and spatial gains, making the selection of insulation material and its optimal thickness a decision that depends primarily on the economic and spatial context of the project. Environmentally, conventional materials achieved higher emission reduction rates compared to aerogel due to their larger adopted optimal thicknesses for all study scenarios presented.