The environmental benefits of relocating buildings

Abstract: As the climate on earth deteriorates, actions are carried out within Europe to limit the amount of hazardous emissions to lower the environmental consequences due to greenhouse gases. A significant proportion of the emissions can be linked to the construction sector and its use of virgin resources. An area with great development potential within the construction sector is linked to its management and generating waste from demolition work. The Waste Hierarchy taken on by the EU states that to achieve sustainable use of resources, waste should primarily be avoided, and further materials should be reused. One strategy to avoid waste and prevent buildings from being demolished is to relocate buildings and thus extend their lifespans. One way to decrease the climate impact of the building industry is to reuse buildings. They can be relocated if they are not situated in the right location. Today in Kiruna, Sweden, there is a major urban transformation where buildings in the city are being relocated to new sites requiring considerable effort and associated procedures. The primary objective of the relocation initiative is to conserve the cultural significance associated with the city. The present study aims to examine the climate impact that may arise from the relocation of a building (Case A) and to compare this impact to that of demolishing and constructing a new structure of comparable size (Case B). This investigation will be conducted through a life cycle assessment (LCA) methodology. As a base for this study, a case building in Åre, Sweden, was assessed using LCA, where the relocation processes were based on interviews with a relocation company. The data collected from the conducted interview formed the scope of Case A. The relocation process was compared to a case study building that was demolished, and replaced by a newly constructed building that will represent Case B. Furthermore, an analysis of various factors, including different energy uses for Case A, calculation approaches for transportation of the relocation, and varying distances for the relocation to different cities utilising different emission factors for district heating was evaluated. To consider the potential benefits of the relocation in regard to the reuse, the amount of materials saved due to the relocation was evaluated, and the climate impact that would have been necessary to reproduce the saved materials was investigated. The results of the LCA for the two cases were divided into two segments. The first segment compared the two cases excluding their climate impact related to the energy use for space heating and domestic hot water use. The outcome of the first segment resulted for Case A in 115 kg CO2e / m2 BTA and for Case B 208 CO2e / m2 BTA. In the second segment, different energy needs were implemented for Case A and Case B to investigate the impact of energy use on the total climate impact. Different geographical locations for district heating were applied with varying emission factors to calculate an climate impact payback time. The results showed that the longest payback time was obtained when the building was relocated to Malmö, which can be linked to the low emission factor for the energy source used in that scenario. The study results show that it is environmentally beneficial to relocate a building instead of demolishing it and constructing a new one. The most significant difference in climate impact between the two cases is related to the reuse of materials in Case A, which reduces the need to produce new materials.