Comparative LCA Study of Preservative Restoration Strategies for 1970s Single-family Houses in Denmark

In Denmark, around 1,700 single-family houses are demolished. These are
buildings that are often built in a period with an architectural style that is appreciated. Still,
poor maintenance, high energy consumption, and too small living units mean the buildings
are increasingly being demolished. The rising rate of demolitions contrasts with emerging
findings that the refurbishment of these buildings not only promotes the preservation of
their historic architectural status but also provides a lower environmental impact
compared to new construction. However, how the refurbishment is carried out is not
unimportant for preserving these values. This study aims to compare the environmental
impacts of four refurbishment strategies, including light biogenic-based restorations to
heavy energy renovations, on a case study of a typical 1970 single-family house in
Denmark that, based on the building techniques and architecture representing typical
1960-1970 construction in northern and western Europe. By assessing these strategies,
we identify the refurbishment strategy with the lowest environmental impact, providing
new insights into sustainable renovation practices through restoration that aligns with
architectural and heritage preservation. Using LCA analyses, the study finds that the two
restoration scenarios emit the least CO2-eq per m2 annually, with the biogenic scenarios
having the lowest impact.