Adaptable load-bearing timber structures

Abstract

The life span of buildings is currently largely determined by economic motives. This often results in a large number of vacant buildings, or unsubstantiated demolition. Since the building industry has the most significant consumption of natural resources compared to other industries worldwide, it is important that the ecological motive gets prioritized more. A strategy to minimize the use of new materials and prevent demolition is to adapt existing buildings to new functional requirements. Current existing buildings are most often not built with the intention to be adapted in the future, making adaptation activities not feasible. Structures that are intented for future adaptation, are mostly focused on complete deconstruction, while most functional changes only require small adaptations. The aim of this research is to develop a framework for the design of adaptable load-bearing structures, focused on adapting individual building components to extend the functional life span of a building. Since there is a level of uncertainty related to the future life span of a building, a scenario based design method is used to formulate different design scenarios to which an adaptable structure should comply. The framework consists of five design domains: material, structural layout, kit-of-parts, building layers and construction process. These domains are explored parallelly on the aspect of adaptation and are evaluated using circular design qualities. The design proposal addresses a structural principle that consists of a primary and secondary connection, in which the secondary connection is used during an adaptation process. The adaptable structural system performs better on the circular design qualities when compared to existing circular systems, mainly on the independency and compatibility. However, the adaptability performance of a building is not solely reliant on the load-bearing structure. This principle only works when the other building layers are also designed with adaptability in mind. This research contributes to the building industry research field by providing a well-rounded overview of factors where adaptability could be implemented into the design process and rethinking the approach to handling the life span of a building.