# Adaptability of Buildings: A Critical Review on the Concept Evolution
## Content Analysis
### Enablers and Promoting Models
#### 3.3.3 The Circular Economy in Buildings
** Design for disassembly is the most discussed strategy in the discourse of circular building design. It implies that all materials and products used at every level in a building can be neatly disassembled and recovered. By this means, building materials and components have the potential to be reused to their highest extent [89]. In addition, the direct reuse of components contributes to both waste reduction and energy savings [2] and would eventually lead to have multiple buildings with multiple lives (closing the loop) and extending drastically the lifecycle of those components (slowing the loop). Adaptable building is also discussed by the literature as a building in which particular components can be changed in response to external factors, for instance users or surrounding environment [12]. In this respect, [PERSON] and [PERSON] [74] suggest that designing for disassembly (DfD) goes hand-in-hand with principles of adaptability. [PERSON] [49] likewise lists designing for deconstruction as a key strategy for adaptability. [PERSON] and [PERSON] [6] find a strong relationship between adaptability and disassembly through the concept of \"Reversible Building\". [PERSON] [65] identifies the scale of building reversibility as a key indicator of circular building that can be figured by assessing the adaptive capacity on three levels (spatial, structural, material) and the reuse potential on three levels (building, system/component, element). When components are designed for disassembly and reuse, a further advantage can be created towards sustainability [12], particularly in reducing costs and environmental impact [3]. By this means, building materials and components have the potential to be reused to their highest extent [89]. The REMs pilot model developed within the BAMB project is an important example of a reversible construction system fully designed for disassembly and to support multiple use scenarios. The model had been assembled and disassembled six times with almost zero waste [90]. Design for disassembly is a strategy that depends to a high extent on the integration of components [4] and how easy they are reachable for safe removal and replacement. In this concern, [PERSON] [7] argues that minimizing interactions among systems' components and creating specified zones for improved physical access to systems are strategies to further promote adaptability. However, this cannot be achieved in old typical buildings due to the inevitable interactions among systems' components that restrain a safe recovery of components and materials of reuse potential. Still, some other strategies may help to retain maximum possible value from those structures, for example, by performing demolition audits for selective deconstruction. The utilization of demountable connections and prefabricated assemblies is an important enabler for disassembly [2, 50], ensuring recovery of materials that are mostly reusable [91] and helping to keep the components of different functions independent from one another [49]. DfD goes beyond the life of a building by addressing the destination of building materials and components [49], accounting for the end-of-life scenarios of buildings at the early design stages [2] that can be an added value to adaptability. * **Standardization and Modularity. ** Standardization is also promoted by the circular economy as an inevitable strategy to promote the reuse of products and materials in multiple structures without essential losses [57]. Meanwhile, modularity has been widely discussed in the literature as an important enabler of adaptability [2, 7, 8, 74, 92]. Designing modular components and building products facilitates the process of disassembly and reuse, and therefore the adaptability [93]. They also reduce the costs [49], waste, and ecological footprint. Replicability of modular units allows for design simplicity, which enables physical modification, spatial rearrangement, reconfiguration, repurpose, and expansion.