Working with material passports
The international pandemic is changing market conditions. Also in the construction sector. Investing in the development of sustainable goods and services is more important than ever. Fortunately, many parties had already embarked on this path well before the pandemic — partly spurred on by the government introducing stricter requirements and legislation, and partly from their own conviction that things could be done better.
BPD Building Fund Property Development already formulated a clear sustainability strategy in 2018 and decided to work intensively on projects that stand out in this area. Buitenoord in Wageningen is such a project with the development of 430 energy-efficient homes. All homes are being built sustainably, natural-gas free, equipped with a heat pump and supplied with a material passport. Residents will know exactly what materials are incorporated into their homes and what the residual value would be in the event of reuse. Last year, BPD set the target of supplying 1,000 new homes with a material passport within one year.
What does this mean for the contractors involved and the suppliers of materials and services who are thus expected to register all these materials and products in Madaster, the registry of materials? We asked Patrick den Boer, BIM director at Trebbe, the construction company that is closely involved in most of BPD’s sustainable projects. In his role, he manages all BIM agreements from A to Z on a project basis and is also involved in model development in collaboration with the subcontractors.
In your position, you are closely involved in realising energy-efficient homes as part of large sustainable construction projects. Are energy-efficient homes the answer to the climate crisis and the resource scarcity we are facing?
Absolutely, with the emphasis on how we build those homes; this is, for example, related to transport movements and production methods. Prefab, for instance, requires fewer people to be present on a construction site and, therefore, also reduces commuter traffic. There is a lot to gain with respect to collaborations with other industries. What, for example, are the possibilities in heat development? Will the current natural gas network be suitable for new developments? Awareness also plays a major role. The fact that we are now registering used materials also means that we are handling them more consciously.
What do you consider to be an energy-efficient house?
A house that is self-sufficient with respect to energy and that can be fully disassembled; completely life-cycle proof. For example, when we find a way for buildings to store energy, we can start considering houses that no longer need to be connected to an energy grid, at which point they would truly be self-sustaining.
You and BPD are currently working on the realisation of Buitenoord, completing around 430 new homes and supplying them with a material passport. How does this affect your work as BIM director?
In terms of the work, things are not very different than usual, because information is always needed. What is new, however, is our close cooperation with BPD and Madaster, and bringing expectations and ambitions together. Being a construction company, Trebbe is mainly focused on the short term, whereas an area developer such as BPD looks further into the future; for example, by choosing to register all the materials being used. This requires a different way of thinking and naturally also brings about a change in awareness. Not just for us, but throughout the entire chain. After all, we also have to ask our subcontractors about the materials they are using. This sometimes leads to pleasant surprises, such as when we discovered that a number of our standard products were already being produced in a very sustainable and circular manner.
Is it not a lot of work if all the materials used also have to be registered in Madaster?
The system is designed in such a way that this requires very little effort. However, in the beginning, because we are concept builders, this did mean that we had to spend quite some time on compiling the library of materials. But now, for all subsequent projects, these things are running much smoother.
It is incredibly important to involve more producers and suppliers in further expanding this library in Madaster. Ultimately, this will result in a more complete and reliable library. From their role in the chain, producers and suppliers can provide more and more accurate information about used products and materials — information that is not always available to us at Trebbe. We really need to send a clear signal to producers and suppliers that such information is needed. Both today and for the future.
The collaboration with BPD and Madaster on material passports is a learning process in which all the involved contractors and service providers are regularly asked for their feedback. What are the main things that you hear from those parties and companies in the chain?
Contractors take a very practical view and, when it comes to linking models and registering data, they want a reliable, well-functioning system, right from the start. To achieve this, however, we do need each other, which requires additional effort and general awareness of the fact that this is the future. As long as working with a material passport is not mandatory, area developers such as BPD can play an important role, in this respect. By including the material passport in project specifications, the entire chain becomes involved. It forces everyone to look much more critically at their own processes and the related long-term effects.
Do you think it is important that completed buildings are provided with a material passport?
With an eye to the future, I think it certainly helps to have insight into the materials used. What is subsequently done with that information is mainly up to our own sector — in both the short and the long term. In addition, the current housing shortage also means that people are particularly focused on the financial benefits. The development of attractive financing options for the purchase and/or development of sustainable houses could make a difference, here.
What do you think is needed if we are to further optimise the process of registering and documenting used materials?
Information from producers and suppliers is needed to compile the most complete and reliable registry of materials in Madaster. This requires a change in awareness. BPD’s efforts have caused a chain reaction which shows that everyone has a role to play in increasing sustainability within the construction sector. As a result, Trebbe is including sustainability as a fixed item on the agenda in its periodic consultations with regular partners, so that they, too, will become more aware of their part in this process. After all, the entire chain is needed if we are to make great strides towards a circular construction economy.