Danish Building Culture and Climate: Investigations of Existing Knowledge on Life Cycle Assessments and Conservation Values in Modernist Multi-Storey Housing 1930-74

The new AR6 Synthesis Report from the IPCC makes it clear that climate change is a growing menace to the planet and to humanity. Building is a major contributor to climate change, since the built environment accounts for approximately 39 % of global emissions, , and the construction sector generates 25-30 % of all waste in the EU. Recent research shows that energy-efficiency renovation may result in lower carbon footprint than new construction. This makes it logical to examine how renovations of preservation-worthy buildings can reduce carbon emissions while retaining or even enhancing conservation values. This was the main objective of the research project called «Building Culture and Climate» (Danish: Bygningskultur og Klima) that was conducted in 2021. Since then, the research project’s topicality has increased, as the EU Commission has presented a proposal for a new building directive on energy performance of buildings.
The project Building Culture and Climate was based on a task description written by the philanthropic association Realdania and carried out as an interdisciplinary cooperation between eight researchers from Aarhus School of Architecture and Aarhus University On an overall level, the project achieved particular distinction for its research, which combined the technical elements of life cycle assessments [LCA] with assessments of conservation values (the value assessment method called SAVE). In general, preservation-worthy buildings are vulnerable to (energy-efficiency) renovation and the modernist heritage in particular, since its holds distinctive, yet delicate architectural values in the exterior that are easily impaired or even lost in renovation.
Consequently, the scope of the research project was to 1) investigate connections between LCA and preservation-worthy buildings (i.e. preservation values or architectural quality), 2) explore the share of preservation-worthy buildings in the total climate impact of existing buildings, 3) examine different energy-saving interventions in the building stock and, 4) look into climate impacts of renovation versus new building which was carried out as case studies.
The aim of this article is to present, discuss and evaluate the above research project. In doing so, the article will initiate an introduction to the overall investigation and clarification of concepts followed by chapters on the systematic literature review, the examinations into the building stock that delimits the choice of cases and, the multiple case study that is based on LCA calculations on different types of energy-efficiency interventions. Then, the article will discuss and evaluate the findings and overall research project and lastly conclusions.
Empiricism is delimited to Modernist heritage multi-storey housing built between 1930-74, since a large part of Danish housing was constructed in this period, has large heat consumption and needs major renovations in the coming years. This project uses the term multi-storey housing about residences with two storeys or more and, horizontal divisions between the apartments. Applied theories and methods relate to architectural heritage such as SAVE, literature studies, case studies and LCA.