How would you build your future home?
How would you build your future home? - Minimizing carbon emissions towards a sustainable future for construction
Concrete that is commonly used in modern construction is one of the most carbon-intensive building materials. How do we build in the future as we want to minimize carbon emissions? Can we make the most of old, traditional construction?
One of the greatest challenges today is to change human activity to match the resilience of the planet. The built environment plays a significant role in meeting these challenges - construction causes 30% of all carbon dioxide emissions in Finland (Construction industry, n.d.) and the construction process itself always causes a carbon spike.
One key factor in reducing CO2 emissions from construction is the use of concrete. Concrete is used in almost all construction worldwide. In Finland, construction technology based on sandwich concrete elements dates back to the post-war reconstruction of the 1950s, when the focus of housing production was on apartment building construction and the projects were implemented as major building concentrations. (Neuvonen, 2006, p.84) In many ways, new construction technology seemed an ideal way to build - it was particularly fast and cost - effective - and was expected to bring solutions to current problems, such as the housing shortage. Before the advent of sandwich concrete elements, the most common construction method in load-bearing vertical structures was a brick wall frame (Neuvonen, 2006, p. 54).
Concrete is still a quite common building material today. A precast concrete wall consisting of different layers of material may seem like a technically competent solution for heat and moisture management, for example, but in reality, the interfaces of the layers are prone to moisture condensation and wall damage. In addition, the service life of different structural layers and thus the need for repair varies. Repair and maintenance are part of normal living in the building, but should we demand more from structures and building materials? Why do solid wall structures last longer than multilayer elements when maintenance-free? If we can build using longer-lasting components, why are we content with elements whose components age earlier than the frame and virtually the entire building envelope needs to be renewed?
Finland has a long building tradition in log construction, which is an excellent example of solid construction - several log buildings over 100 years old have survived to this day. Today, solid wood construction in Finland is still in its infancy, even if material can be found in Finnish forests. Today, solid wood construction is well established in a few European countries, such as Germany, Austria, and Norway. Solid wood elements are the result of product development in which health at all levels has been taken into account: solid wood elements consist only of mechanical joints and do not contain substances harmful to the environment, such as adhesives or plastic films (Mattila, 2014, p. 43). In the future, Finland would have a really good opportunity to develop solid wood construction within the framework of existing industry and materials.
In addition, the advantage of timber construction from an environmental point of view is that the timber building acts as a carbon sink. The volume of wood construction should be increased, and the use of non-renewable natural materials reduced. However, the most important solution for reducing a building's carbon footprint is simple: buildings should be used longer (Toivonen, 2017). We know enough about the history of the properties of different materials and structures so that in the future we can avoid past construction mistakes and make our buildings as long-lasting as possible.
Finland's goal is to be carbon neutral by 2035. Achieving an ambitious goal is challenging if we do not make changes to our ways of building and rehabilitating the built environment. We need to build sustainable, long-lasting, and serviceable buildings. Repair should always be the first option rather than disassembly. The problems of modern construction must be recognized at the latest now. We have the opportunity to learn from the old building tradition and avoid the mistakes of the past. What kind of future do you want to see? - You Tell Me.
Sources:
Mattila, L.-E. (2014). Tulevaisuuden kerrostalo. Master’s Thesis. Aalto University.
Neuvonen, P. (2006). Kerrostalot 1880-2000: Arkkitehtuuri, rakennustekniikka, korjaaminen. Rakennustietosäätiö RTS, Rakennustekniikan keskus ja -säätiö. Museovirasto. Helsinki: Rakennustieto.
Rakennusteollisuus (n.d.), Rakennettuympäristö ja ilmastonmuutos [verkkoaineisto]. Accessed [17.9.2020]: https://www.rakennusteollisuus.fi/Tietoa-alasta/Ilmasto-ymparisto-ja-energia/Materiaalitehokkuus/
Toivonen, J. (2017). Sementti on isompi ilmastopahis kuin lentokoneet, ja nyt se pitäisi korvata - mutta miten? Tehtävänä tulevaisuus. Yle Uutiset. Accessed [30.9.2020]: https://yle.fi/uutiset/3-9901767