Design for Disassembly in housing: the need to adapt LCA to Shearing Layers

Abstract

The current lack of sustainable and affordable housing is a global issue which has reached a crisis point. Traditional construction approaches used to solve sustainability issues in housing are often in tension with affordability, where the achieving one of these two aims is often to the detriment to the other. The application of Design for Disassembly (DfD) in combination with Industrialised Construction (IC) can simultaneously provide environmentally and economically sustainable solutions to these ongoing housing challenges. However, the application of DfD and the planning of varying lifespans for different building components raises issues with the conventional Whole Building Life Cycle Assessment (LCA) methodology, which is used to quantify environmental impacts of the construction.This paper covers three theoretical objectives: (1) to provide an overview of DfD and IC and how these can be combined to provide resource efficient, affordable housing (2) examine how the Shearing Layers concept can extend the building lifespan and better ensure a sustainable End-of-Life, and (3) a preliminary outline proposal as to how the Whole Building LCA methodology, based on existing standards, can be adapted to align with the Shearing Layers. These objectives will be achieved through a literature review, covering the theoretical principles of DfD and the key ISO standards related to LCA. Based on the literature and applied theory, a preliminary aggregated LCA methodology is proposed that will be further developed and tested using case studies in future investigations by the author.The result of the discussion reveals potential conflict between construction in practice and applying Shearing Layers and the adapted Whole Building LCA and the need for further investigation to establish the number of years assumed for each layer of the LCA. Whilst inventory data for materials and processes follow conventional practices, it is the proposed organisation of information into layers illustrates to designers the need to design housing for disassembly to remove and replace building components.