# Adaptability of Buildings: A Critical Review on the Concept Evolution
## Content Analysis
### Interpreting the Concept of \"Adaptability\"
Scholars discussed multiple types of change such as change of use or function (to the same or to another use type), changeable parts or components, space plan, layout, size or volume, and performance changes. However, change of buildings' use is the dominant type in the literature [1,3]. This is probably because users frequently tend to adapt the usability of their spaces to match their needs by their own, through conducting simple modifications (e.g., changes in furniture). In this respect, several studies perceive adaptability as a person-centric action triggered by user attitude to accommodate change, for example, by changing the use of one space [25,36]. Still, other changes in uses or functions may call for professional intervention in order to perform larger or more complex alterations, particularly when changing to another function (e.g., from office building to housing). Understanding these change factors is key to the development of buildings that are adaptable over their lifecycle [37]. The ideology of change in its various types is coherently associated with the concept of adaptability in literature dialogues, making it an umbrella concept to strategies and concepts linked to one or more of change scenarios such as extendibility or scalability, flexibility, recyclability, reusability, transformability, upgradability, convertibility, and durability, among others. Operational conditions may change at any point over the lifecycle of a building just as different needs of users may arise. The static nature of conventional buildings ignores the provisional nature of architectural objects manipulated by the previous variables within a certain context. Incorporating adaptability thinking therefore calls for shifting the direct focus on form and function defined by actual needs towards contemplating long-term changes against a time perspective. [PERSON] [38] affirms that implementing adaptability does not imply a one-time solution but should allow for various possibilities overtime. Similarly, [PERSON] et al. [30] consider that adaptability seeks a reconceptualization of time through switching attitudes and rethinking values. The time factor is hence considered a key enabler for change, allowing buildings to be perceived as dynamic systems that react in response to emerging needs [39] with long term consideration of the sustainability of the built environment. Adding a time factor to the design process stems from creating a certain context where a building is prone to the temporal reality of architecture in the face of change [30]. Adaptability thus involves additional knowledge of context conditions, purpose, and application, which may not be as clear at first glance [40]. Decisions about design and construction process of a building are usually derived from immediate needs and conditions, thereby shaping a certain context. Incorporating a time-based approach assumes that contextual conditions are not of a stable nature. [PERSON] et al. [40] confirm that successful adaptability strategies anticipate how contextual factors change over time. The contemplation of context enhances the capacity to be modified to fit new conditions, which is another quality of adaptable buildings discussed by several authors such as [PERSON] [32]. The fit in a traditional building is restricted to the limits of function and form defined by immediate considerations, while for an adaptable building, the fit is context-oriented and time-based [30], providing fit scenarios to both actual and future considerations. A key objective of adaptability is the ability to prolong the useful life time of a building [31]. Most buildings become obsolete before their technical life comes to an end, thus being abandoned. This happens due to the discrepancy between the conditions of supply of space and the demands varying overtime [40]. A mere long-life building does not matter without a utility provided to its users.