Document Type : Research Note


Department of Civil Engineering, Chalous Branch, Islamic Azad University, Chalous, Iran.



Building insulation stands out as one of the most widely employed strategies to enhance energy efficiency in the building sector. Increasing the thickness of thermal insulation is a conventional approach to meet the design requirements of these structures. In this study, a novel approach to augment the thermal resistance of external building walls is explored by simultaneously employing multiple thermal insulation materials, comparing this with a single-layer insulation setup. Three typical insulation materials with varying thicknesses are utilized to create a three-layer insulation system, which is applied to a case study involving a house-like cubicle situated in the 3B climate zone per ASHRAE 169-2006. The findings indicate that merely increasing the thickness of a single-layer insulation does not invariably yield optimal solutions. The results emphasize that the consideration of multi-layer insulation systems can establish a continuous decision-making space, enabling the identification of at least one insulation scenario aligned with design requirements. To facilitate designers in the initial stages of thermal insulation design, a rapid and simplified design model has been developed based on the results. The methodology proposed in this study is generalizable and can be applied to all climate zones, offering a comprehensive design tool without the need for intricate calculations.


Main Subjects

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