As a matter of principle, the Deutsche Gesellschaft für Nachhaltiges Bauen (DGNB) is neutral when it comes to material selection. The main objective of the holistic DGNB certification is to ensure that the right materials and methods are used for a given project, based on the buildings use, type and location.
Still, Christine Lemaitre, CEO of DGNB e.V., regards the increased interest in using wood as a main material for building construction as a positive development, as it provides more options and variety for the architects and developers.
– Wood certainly has specific advantages when it comes to sustainable building, such as the CO2 footprint, flexibility and deconstruction ability. So, it is positive to see that wood is once again becoming a major material in larger constructions – not just for decoration or interior furnishing, but as part of the structural systems, says Christine Lemaitre.
A driver for innovation
Christine Lemaitre is confident that the rediscovery of wood will be a driver for innovation in the building industry.
– Architects are starting to experiment with wood as part of their design and integrating wooden structural systems into the interior design of the building. For instance, instead of the wood being hidden behind paint or drywall, it is left visible as part of the design.
However, Christine Lemaitre points out that besides design and structure, there is also a need for innovation that focuses on the end of the building’s lifespan.
– In terms of deconstruction and recyclability, what can you do with the wooden elements, once their original use is over? That question, in a circular economy context, is highly relevant for basically all building materials right now, says Christine Lemaitre.
Wood counts positively towards certification
If you want to obtain a DGNB certification for your building project, there are several reasons to consider wood as an option. If a substantial amount of wood is used in the construction, the life cycle assessment will reflect it in a positive way, because wood is a low-carbon material compared to other common materials for structural systems, such as steel or concrete, which are more carbon-intensive.
The flexibility of the building is also a criterion, as is deconstruction and recyclability, and in all these areas, wood can have a positive effect on the evaluation. This also applies the responsible sourcing category, if the proper care is taken when selecting building materials.
– For wood to count towards responsible sourcing, it needs to be FSC or PEFC certified. The climate goals are one of the main drivers for the increase of wood, and the FSC and PEFC certifications are essential tools to ensure that we do not destroy one part of the environment to improve another, says Cristine Lemaitre.
More DGNB-certified wooden building on the way
Right now, the first DGNB-certified building with wood as a part of the main structure is under construction, and Christine Lemaitre expects to see an increase in DGNB-certified buildings using wood in the coming years.
– We have some interesting examples already, like the new Alnatura Campus in Darmstadt, which is the largest rammed-earth building in Europe. The exterior walls are made of rammed-earth and the roof construction out of wood. This is a very good example of different natural materials being used in a very sustainable way to create a very high-quality building. We have also pre-certified a wooden 4-5-storey residential high-rise building in Heilbronn, as part of the German National Garden Show 2019. OVG’s Southcross Berlin building will also have a wood structural system and is already pre-certified to Platinum. So, we see more and more wood being used in interesting and different ways.