Heritage Conservation and Environmental Protection: Conflicting Interests in a Case Study of Historic Box-Type Windows

Heritage conservation and environmental protection have similarities, both aiming at conserving structures and systems in their original state. While environmental protection prioritizes intact ecosystems, heritage conservation values past cultural achievements, thus reflecting the difference between nature and culture. Our research purpose is to analyze the interaction of these two disciplines for historic windows, which can be renovated, technically upgraded, or replaced by a new window. As the methodology, an LCA model was applied, where, after defining a model window material and energy flows in three scenarios, the related environmental impacts were investigated. The results show that the considerably lower loss of energy with a new window by far outweighs the impacts from the production of the new window. This becomes apparent for nearly all impact categories. The sensitivity analysis reveals that the energy source for heating has a major impact. Changing from fossil to renewable energy in the future will reduce the advantage of new windows markedly. Such novel approaches should support the integration of environmental considerations into heritage conservation.