End-of-Life Challenges in Façade Design

Abstract

In recent decades, there has been increased attention to reduce the operational energy performance of buildings. Stringent legislation on building energy performance has stimulated facade design to evolve to serve numerous functions and meet complex technical requirements. This has in part been achieved by an increase in the use of materials, processing methods and construction techniques, which paradoxically may reduce the ability to recover material that is high-value in terms of embodied carbon after its first use. Existing environmental assessment methodologies assign accreditation for the use of low embodied carbon materials associated with re-use and re-cycled products in the input and production stage (module A), however, the ability to recover the materials and associated environmental benefits as a function of design, also known as reclamation potential, is not usually considered. This study aims to develop a robust disassembly assessment framework to evaluate the reclamation potential of materials from facade systems and forms part of a larger ongoing research program to address the end-of-life challenges in facade re-use. The disassembly methodology will allow the reclamation potential, in terms of environmental impact, of different facade designs to be assessed as a function of time in terms of component and system service lives, with reference to different recovery scenarios. The proposed methodology has been applied to a reference system; the ubiquitous insulated glazing unit (IGU), with a reference service life of 25-years, to highlight some of the potential future applications of the assessment framework. Preliminary findings show that service life and early-stage design constraints can hold great influence on determining the recovery strategy that yields the greatest reclamation potential for systems at end-of-life.