Refurbishment potential of office facades

Summary

Two thirds of the office-stock in Western Europe is older than 30 years. At this age façades and technical installations reach the end of their technical life-span and buildings show a very bad performance in terms of user comfort and energy consumption. This situation leads to a high demand for refurbishment of office buildings constructed between 1950 and 1980. The research project aims to find and evaluate strategies that support a refurbishment of office facades that is both feasible and sustainable.

Background

The load bearing structure of a building can often last for centuries. The interior is renovated whenever desired by the tenant. It is mostly the façade and the technical installations that approach the end of their technical lifespan at the age of 30. With the current discussion about energy (and money) saving, many planners have encountered the topic of refurbishment as a more sustainable option than demolition and new construction. Unfortunately, the most common form of refurbishment is to strip the building to the load bearing structure. This is often not very sensible, as it forces the users to move out of the building, which again causes nuisance and extra costs. Our research has shown that there is room for plenty of other solutions.

Description of the research project

In a first step, the current market of office buildings in Northern Europe was assessed. This delivered an overview of the quality and quantity of different façade typologies. Based on these results, we analysed representative buildings of each common typology and developed different refurbishment strategies for each building in close collaboration with building owners and users. A comparison of these strategies in terms of energy consumption, impact on the building structure and the office use, as well as an estimation of life-cycle-costs delivered a collection of strategies more-or-less suitable for different possible situations.

Facade-refrubishment before - after

The picture shows a university campus today and as it could look in the future. Façade refurbishment does not only treat the façade, but has to find synergetic effects for the entire project.

Practical application

The stock of office buildings in need for refurbishment in the Netherlands sums up to over 25 million m² GFA. If these buildings saved only 10% of the energy they consume today, 170 million kg of coal could be saved per year. But, running energy is only one aspect: replacing a structurally good building also causes a waste of material and embodied energy. Furthermore, it can be a loss of architectonic identity. This research project has also shown that it often is a waste of money too. Based on our results it will be possible to predetermine, which strategies of refurbishment are the most appropriate for which type of office façade. It will answer the question of “how to judge, how to refurbish”.

Contact

If you want to know more about the potential of underestimated elder office buildings, do not hesitate to contact us at:

Chair Design of Construction

Faculty of Architecture

Prof. Dr.-Ing Ulrich Knaack

Dipl.-Ing. Thiemo Ebbert

Email: T.Ebbert@tudelft.nl

Internet: www.doc.bk.tudelft.nl