"With a click on a BIM object, the user knows its reuse potential"
Dutch architect and founder of the 4D Architects, Elma Durmisevic has been working for 20 years on the reversibility of buildings as well as on the reuse of their materials. This work has enabled her to design a specific BIM tool.
Where does the idea of using BIM to evaluate the reversibility of a structure come from?
I've been developing protocols and tools to design reversible buildings for 20 years. I finally developed a digital tool that measures the potential for disassembly and reuse of building products and materials. It was formalized as part of the European research project "Buildings as a material bank" completed in 2019. This tool takes into account the interdependencies between materials and volumes of a building.
I also developed eight indicators of reversibility and material reuse potential that provide a final score on reuse potential. The last step, to make the tool more user-friendly, was of course to use digital technology to process all this data.
Which buildings are concerned: existing buildings or those to be built?
The "reversible BIM tool" is suitable for both new designs and the transformation or deconstruction of existing buildings. Designing reversible buildings implies a systemic change in the design, but also in the way of building and maintaining the structure. To make this transition, decision support tools are needed, hence the development of a specific kit for designing reversible buildings. It also includes a section on the reuse of materials during deconstruction.
How does the "Reversible BIM tool" work?
For the input data, we need a 3D scan of the existing building and the resulting point cloud. This then allows us to create a BIM model with a view to reversibility. Once this model is created, plugins analyze the relationships between the elements of the building and their dependency on each other. In the end, we use a color code that represents the reuse potential and/or reversibility score for each object. By clicking on the objects, the user gets information about the reuse potential, dimensions, volume and even CO2 emissions saved.
Were you able to identify assemblies that were more relevant than others?
Designing a reversible building means assembling independent elements and linking them with connections that are themselves reversible. It is better to bolt floor slabs together than to cast them in place, for example. In each case, the elements must be replaceable without affecting the surrounding parts. Their replacement should not involve demolition.
What are the main advantages of BIM for assessing reversibility and reuse potential?
Once modeled, the evaluation of reuse potential becomes much faster with BIM than manually. The advantage of the "Reversible BIM tool" is that it allows to select all the elements with high reuse potential before deconstruction and to create a library of BIM objects. Architects can then use these in their new designs. This can stimulate the use of reusable elements in the future.
Is your solution available in France?
Currently, it is still a prototype that few insiders are testing. We are developing a platform on which the tools and protocols will be made available to a wide audience. The whole system will be evaluated by the end of 2021 for wider use, particularly in France. Many adaptations will then be necessary.