Future proof buildings

Abstract

The built environment has an important role to play in sustainable development. The Dutch government estimates that the build environment is responsible for 50% of resources used, 40% energy use, 30% of water use, 35% of CO2 production and 40% of the total waste production in the Netherlands. Because of these relatively high numbers, changes in the build environment can have large impact on the sustainability of our society.
At this moment about a hundred thousand dwellings built during the 1960 -1970 are reaching the age of 50 each year making more than 50% of the Dutch building stock older than 50 years. In the current Dutch building stock, only a small portion of new buildings is added every year. At the current rate of 0.4% it would take 250 years before all buildings would be renewed. The average lifetime of a residential building is 50 years. This can be extended another 50 years with the right intervention. It is therefore very important to have a solid strategy to deal with existing buildings as this can play an important role in maintaining a high-quality building stock while working towards sustainable goals.
This thesis looks at the challenges of high rise residential flats built in the post- WW2 era of the 1960’s in order to develop a refurbishment method that can help to upgrade and maintain these types of buildings in a sustainable way. By keeping the buildings instead of demolishing or replacing them resources and energy can be spared and by refurbishing them a more sustainable building stock can be achieved.
The chosen refurbishment method is an add-on strategy as this deals with many challenges the flats are facing. Using the parameters from the case study project the Leeuwerik flat in the Poptahof, add-on variants have been designed with big emphasis on flexibility, demount ability and durability. The Add-ons aim to improve the physical building qualities by providing better thermal performance. They improve the spatial qualities by providing extra space and they improve the social quality of a building by provide a new and more diversified look.
The three main add-on variants are categorised by material namely wood, concrete and FRP. The add-ons have been detailed to be completely prefabricated and to be quickly mounted on the building. The performance of each of the addons has been assessed in order to compare them and to find out what the influence is of the material choice on add-on dimensions, the thermal performance the and the environmental performance.
Overall it can be concluded that using a demountable add-on strategy is a feasible way to quickly refurbish a building. It offers a way to deal with existing building physical problems and can improve the architectural and spatial qualities of an existing building. Different add-on types and construction materials and are possible. This leaves a lot of space for designers that want to use the demountable add-on strategy while working on a refurbishment project of a high rise residential building to make their own choices depending on the focus of the project, giving each building a unique appearance. This will lead to a higher quality and more sustainable building stock in the long run.