The unspoken: Architectural values, material flows and renovation of modern housing stock

Paper in proceeding, 2015

Renovation activities account for over 40% of all activities in the building sector and there are indications that these activities will increase in the near future driven by the need for modernisation of large stocks of post-war housing and objectives for energy efficient renovation. The renovation process is complex, involving many stakes and stakeholders and there is a lack of knowledge about renovation options that results in long-term sustainability. One area that is un-researched is material flows driven by renovation, the so called ‘dark-side’ of renovation. Recent studies of new buildings show that up to 50% of the total energy use of buildings can be derived from built-in or ‘grey’ energy, facts that emphasise architectural design and its contribution to a more sustainable built environment. There are also indications that unwise architectural decisions lead to the replacement of existing, and often still functioning, materials and building components with new that have shorter technical and aesthetical life resulting in increased material flows as well as losses of architectural and historical values. Based on 5 illustrative cases, this paper reflects on the long-term durability of architectural and technical choices made in renovation with a focus on exterior changes and materials. Results show that materials do not always perform as predicted and are replaced or in need of maintenance earlier than expected. Our (R)solution is that long-term sustainability of architectural solutions proposed through renovation is an area in need of further research.