Climate adaptation and mitigation in the building sector: towards a sustainable built environment

Abstract

The principal objective of this PhD study has been to investigate climate adaptation, climate mitigation and sustainability in the building sector, mainly focusing on existing buildings.

The presented work examines climate adaptation, risks, and consequences of climate change for different climate parameters that are particularly important for the built environment in Norway. This examination proceeded by first developing an approach (or methodology) to impact assessments for buildings in a changing climate. Furthermore, case studies on risks and consequences of sea-level rise and changes in outdoor temperature and precipitation (rot decay) are presented.

The study on sea-level rise shows that as many as 110,000 buildings in Norway are situated less than 1 metre from current sea level. When compiling the number of buildings situated close to sea level in different regions and the predicted sea-level rise towards the year 2100 (scenario), the greatest risk found is associated with the counties in the western part of Norway. Extensive measures on existing buildings and strict regulations on new buildings/infrastructure are essential to preventing large economic losses in the future.

The case study on temperature and precipitation changes (rot-decay risk) shows that, in 2100, 2.4 million of today’s existing buildings in Norway will be situated in a climate zone with a high risk of rot decay. This is a significant increase compared to the 615,000 buildings located in this climate zone today.

The study on climate adaptation shows that requirements for robust constructions and more attention to different climatic zones in building planning must be of high priority in the years to come. Also, changes in local building practices should be expected. As the consequences of climate change for buildings could be quite dramatic, better tools and guidelines on vulnerability analysis should be developed, for the benefit of public and private planners and building owners. This study offers new and improved approaches and methodologies for impact assessments on buildings in a changing climate. While making building data and climate data more easily accessible, this research also forms a solid base for further investigations and research on climate adaptation of buildings in Norway.

The objective of the study on climate mitigation and sustainability was to investigate how mitigation measures (primarily energy efficiency) are positioned in typical refurbishment projects and to identify which other parameters should be included in order to achieve sustainable refurbishment. This investigation was accomplished through a Nordic research project that aimed at developing a guideline for building owners on how to do sustainable refurbishment.

First, several Nordic case studies of refurbishment projects were investigated to identify barriers and challenges. The findings crystallized important topics to focus on in a guideline.

Next, a set of approximately 70 indicators was established to build a framework for a 10-step guideline mainly focusing on process, sustainability, ambitions, strategy, performance profile (condition survey), strategic analysis, and target setting. The work offers detailed studies on both the building owner’s strategies and the building object itself. It also gives a thorough description of the challenging task of selecting indicators, weighting indicators, and defining zone-values as input for further research on sustainable refurbishment of buildings