Double-Skin Façades for the Sustainable Refurbishment of Non-domestic Buildings: A Life Cycle Environmental Impact Perspective

摘要

In developed countries, existing buildings have the biggest share in the building stock. Given the age of construction, the property versus land values, and their slow replacement rate, low-carbon refurbishments are arguably one of the most sensible ways to mitigate environmental impacts (EIs) in the construction sector and meet the greenhouse gas (GHG) reduction targets. In this respect, Double-skin façade (DSF) has been defined as one of the most effective ways to efficiently manage interactions between outdoors and indoors, and its benefits span from passive heating and cooling to the enhancement of thermal comfort of the occupied spaces. A plethora of research does exist on the operational behaviour of the DSF. However, life cycle energy figures and EIs are yet to be established fully and comprehensively. This paper reports on findings of an on-going research project aimed at filling such a gap. More specifically, life cycle assessment (LCA)and building energy modelling (BEM) have been combined to build a methodology to help assess life cycle energy figures in a more holistic manner. Primary data have been collected from manufacturers from across Europe about all the life cycle stages and processes related to a DSF refurbishment. Results show that if on the one hand, the life cycle energy balance actually is negative, hence supporting a wider adoption of DSFs in refurbishments, on the other hand, there exists ecological and EIs that the DSF bears; that cannot be easily overlooked if a more responsive approach to the EIs is to be undertaken. Not only do these findings inform a more energy-efficient deployment of DSFs, but they also highlight the need for a more holistic and impact-driven design approach to ensure that the environmental burdens are not just shifted from one impact category to another.