Thesis: Adaptive reuse of the built heritage
Hvita korset, Älmhult 2022 © Camilla Häggman
Adaptive reuse of the built heritage – an investigation of reuse as a conservation method for a sustainable future
The thesis reviews the prerequisites for an increased use of adaptive reuse as a conservation method for cultural heritage buildings. It argues that in order to reach Swedish and international climate goals, adaptive reuse is a crucial tool to limit greenhouse gas emissions from the construction and demolition in the building industry.
Thesis summary
According to the Swedish National Board of Housing, Building and Planning (Boverket, 2020) the building industry (construction, demolition and materials) amount to approximately 20% of Sweden’s total greenhouse emissions (Boverket, 2020). The Swedish climate law (SFS 2017:720) from 2017 is a national response to the global agreement that was specified in the Paris agreement from 2015. The Paris agreement states that forceful economic and social changes need to be implemented to reach the goal of limiting the global warming to 2° (UNFCCC, 2015). According to the Swedish climate law the government will implement changes to lessen greenhouse gases in our atmosphere. Sweden’s climate policies support the long-term goal for Sweden to have zero net emission of greenhouse gases by 2045 (Mål för miljö och klimat, 2020).
One of the tools to reach the climate targets of the Paris agreement (UNFCCC, 2015) could be more extensive recycling and reuse. In this context adaptive reuse of the built heritage, meaning the process to renovate and adapt existing houses for new purposes (Wong, 2016, s. 30). Approximately 85–95 per cent of existing buildings in Europe (over 220 million structures) was built before 2001 and will still be in use at least until the year 2050 (European Commission, 2020, s. 1–2). The current research in the field of heritage and adaptive reuse has a focus on climate issues and the challenges that we face to reach the climate targets while the earth’s population is still growing and in need of housing (Lynch, 2022, s. 8).
Today we create, use and demolish buildings according to a linear life cycle which uses a lot of resources in raw materials, energy during the building process and waste and loss of energy in demolition. (Foster, 2020, s. 2–3). Meanwhile we have existing, unutilized built former industrial buildings, public buildings, offices and abandoned private houses that lack purpose (Ahlqvist, 2019, s. 4). Instead of demolishing these buildings, which have already burdened the environment with greenhouse gas emissions, it would be possible to apply adaptive reuse as a way of reusing the buildings and at the same time care for the cultural heritage in built environments (Foster, 2020, s. 2–3).
An increased reuse of our built heritage could be used as a strategy and a method to reach the Swedish climate targets (SFS 2017:720) and by extension the global targets stated in the Paris agreement (UNFCCC, 2015). It could be used as part of a future circular economy and at the same time protect of our built, cultural heritage.
Images © Camilla Häggman 2022, except historical images from Digitalt muesum.
The thesis reviews two case studies in Sweden, one of which serves as an example of successful implementation of adaptive reuse, located in Västerås, while the other case study presents the challenges inherent to adaptive reuse, located in Älmhult. It also includes a review of relevant literature and research papers in the field which further explore the changes that need to be made on a societal level and within various regulatory frameworks for adaptive reuse to be more viable.
By examining the local governments in Västerås and Älmhult and their attitudes towards adaptive reuse a few challenges and possibilities have been identified. This was done with the help of an online survey. Some of the challenges consist of higher costs related to renovation than new builds, difficulties to adapt existing buildings to current building standards and issues related to city planning and regulations. Some of the possibilities consist of environmental benefits by not using new raw materials, financial benefits by making use of the investments that has already been done in the built environment and cultural, esthetic and cultural values that comes with historical buildings (Häggman, 2022).
“The greenest building is the one already built” Carl Elefante, architect
Older buildings are often referred to as environmentally unsustainable because of their lack of insulation. Therefore, there is a belief that the best for the environment would be to demolish these buildings and replace them with newly built energy efficient buildings (NGBC, 2019, s. 11). Research shows that this is incorrect. The architect Carl Elefante said “the greenest building is the one already built” (Lynch, 2022, s. 8). With this quote Elefante means that greenhouse gases are ”locked” in built structures, so called ”embodied greenhouse gas emissions”. By reusing buildings, we can prolong the lifecycle of these structures, thereby lessening the need for new materials and the environmental costs that are connected to transport and demolition. By extending the buildings’ lifecycles with a heritage approach we can reevaluate” worthless” buildings from a material, social and cultural perspective.
Studies show that adaptation and reuse of built heritage use up to less than 50% less greenhouse gases than new construction. For a new energy efficient building it takes up to 80 years before it has compensated operationally for the energy used at construction. (Arfa m.fl., 2022, s. 16). Calculations also show that it’s vital to reuse buildings that consist of a large amount of steel and concrete due to the environmental impacts they have as raw material. Other possible changes that can be made to lessen current buildings’ environmental impact is to update ventilation, insulation and heating systems. (NGBC, 2019, s. 11–12).
To meet Swedish climate targets for 2045 of zero net greenhouse emissions we need to adapt and reuse existing buildings in a circular and sustainable way. Instead of focusing on current buildings’ energy debt as something negative, we can shift our perspective and see the potential of these resources and the possibilities of reuse in the future (Arfa m.fl., 2022, s. 16). The thesis concludes that while certain challenges exist, an increased use of adaptive reuse is possible and desired if cities, regions and countries are to lower emission levels and at the same time protect and retain valuable cultural heritage within societies.
Department of Conservation
conservation.gu.se
Program in Integrated Conservation of Built Environments
Graduating thesis, BA/Sc, 2022
By: Camilla Häggman
Mentor: Bosse Larsson
Title in original language: Adaptiv återanvändning av det byggda kulturarvet – En undersökning av återanvändning som kulturvårdsmetod för en hållbar framtid
Language of text: Svenska
Number of pages: 60
Keywords: Adaptive reuse, building adaptation, built heritage, urban planning, conservation methodology, climate goals
Sourcing can be provided by request
Download link for the thesis at GUPEA
