Building on
Building with and within existing structures has a very long tradition and is more important today than ever. Dealing with our existing building stock is a highly relevant aspect for climate protection and it will be one of the biggest challenges for our industry in the coming decades. The decisive factor in this context is not our buildings’ operation but the hidden grey energy over their entire life cycle.
The most sustainable building is therefore the one that is already there. As much as the remodelling and extending of buildings is a challenge for architects and all those involved in planning and construction, it also holds and demands a great deal of creativity and flexibility, inspiring new and exciting ways to build.
Far too much intact building fabric
is still being destroyed and
replaced by new construction.
Missed opportunities
Cities around the world are looking for ways to provide sufficient space for their rapidly growing urban population. In order to meet this demand, urban and municipal planning must activate the existing building stock as a basis for new developments. The issue of urban densification is directly linked to issues of energy and resources. The term „circular construction“ being omnipresent and much-discussed at the moment is a good thing. Nevertheless, far too many intact buildings are still being destroyed and replaced. While we wait too long to carry out repairs, we miss the opportunity to reposition our rich building stock for the future of our building culture. This applies to the function, structure, systems and aesthetics of a building. We successfully seized this opportunity at the Music & Congress Centre in Strasbourg.
Hochreute Estate, Immenstadt, © David Matthiessen
Life cycle and lightweight construction
as part of the solution
One aspect of the solution are systematical changes over a building’s life by upgrading them in order to meet the changing new requirements such as the former Hochreute Estate. Building within existing structures does not only mean modernising, neither is it only about extending them or adding storeys on top. It means developing sensible conversions. The best way for us to honor the history, origins and special features of existing buildings is to ensure that their continued use meets both today's functions and tomorrow's expectations. The Angelika Kauffmann Museum, for example, was created from a listed farmhouse. The demolition of an existing building must be properly assessed in order to take an informed decision whether it makes more sense to extend the use of a building or to recycle its components - depending also on the extend to which this is possible.
Particularly important within this context is the preservation and the continuing use of the existing load-bearing structure; This is also, where lightweight construction, building and extending with wood play an important role. Studies show that around a quarter of existing buildings would be strong enough to support additional storeys made of wood. A timber frame extension can be quick, sustainable and cost-effective. Their high degree of prefabrication make them predestined for inner-city construction sites that require short construction times and as little nuisance as possible. We successfully utilised these advantages back in 2006 for the Flachgasse roof structure in Vienna.
Full of surprises
Be it conversions, extensions, renovations or refurbishments - we as a practice have been able to acquire a lot of experience in this field since our early years. This still serves as a valuable resource for all current and future projects. Nevertheless, building in existing structures is full of surprises and these processes remain always exciting. Every project - regardless of its size and importance -holds a new opportunity to reflect, emphasise and promote socio-cultural and ecological values.
Text: Barbara Fontana, February 2024
