Optimisation of the insulation thickness for the external walls in Morocco while considering the effect of climate change

Abstract

The rise in global temperature is a direct consequence of the climate change phenomenon, whose effect on building energy demands can no longer be neglected. In this regard, thermal insulation is considered an efficient design measure to enhance the energy performance of buildings. The key factor for the cost-effective implementation of insulation in buildings is the proper selection of insulation thickness. However, the consideration of the climate change factor in the optimisation of the insulation thickness for building walls has not yet been addressed by researchers. In this work, the optimum insulation thickness of different wall façades is calculated in three principal climate regions in Morocco, while taking into consideration the effect of climate change over the building lifespan. The calculation used a dynamic life cycle costing method to consider the varying climate conditions over time. The future weather data is elaborated based on the medium–low greenhouse gas emissions scenario RCP4.5 of the intergovernmental panel on climate change fifth assessment report. The obtained results show that the optimum insulation layer thickness would vary between 0.04 m and 0.07 m depending on the wall orientation and the climate zone. Considering all walls, the life-cycle energy saving ratio would vary between 49.64 % and 54.87 %.The economic feasibility analysis indicates the payback period would be less than 10 years regardless of the wall orientation and the climate zone. In addition, it is shown that the effectiveness of the insulation would not be adversely affected by the climate change phenomenon in the future.