Legal requirements and opportunities of circular construction
Dr. Christine Lemaitre talks to lawyer Michael Halstenberg about the legal framework for construction products, the reuse of materials and the practical challenges of circular construction – and shows how new standards can pave the way for more sustainable construction.
Why circular construction is so important
Circular construction means planning and implementing buildings in such a way that materials can be used, reused and recycled for as long as possible. The aim is to avoid waste, conserve resources and significantly reduce the environmental impact of construction.
During the discussion, it becomes clear that, legally speaking, there is currently little distinction between new, used, sustainable or circular building products. The only decisive factor is that building products meet the applicable technical requirements – regardless of whether they are new or reused.
Circular construction means that materials are not disposed of after a single use, but are repaired, reused or recycled. This creates cycles instead of waste.
Legal requirements for construction products
Building law in Germany sets clear requirements for construction products, especially if they are relevant to safety. These include, among other things:
• Stability
• Fire protection
• Thermal and sound insulation
• Health protection (no harmful substances)
These requirements apply to all construction products – regardless of whether they are newly manufactured or come from demolition.
Many simple components such as door handles, skirting boards or nails are unproblematic. However, as soon as safety-related properties are affected, performance values must be known and verifiable.
Construction products must be safe. They must not pose a risk to people and must meet minimum technical standards – even when they are reused.
Material passports: transparency for every construction phase
A key topic is material passports: these document which materials are used in a building, their quality and how they can be reused later. The discussion shows in a practical way how material passports are created and what added value they offer for planners, builders and owners.
New Construction Products Regulation: A first step
The new EU Construction Products Regulation EU-Bauproduktenverordnung has been in force since 7 January 2025. It applies directly in all Member States and addresses issues such as reuse and recyclability for the first time.
However, it is currently of little practical help. Only when new mandates are issued and harmonised product standards are developed on the basis of this regulation will concrete requirements for manufacturers arise – and with them clear framework conditions for circular construction products.
The new Construction Products Regulation is intended to pave the way for more reuse and recycling in the construction industry in the long term. However, concrete standards are still largely lacking.
Reuse of building components: What is the status quo?
In practice, reuse is most common where materials can be easily tested. These include, in particular:
• Steel beams
• Solid wood
• Some reinforced concrete components
Guidelines and initial standards already exist for these materials, for example from Brandenburg or the Karlsruhe Institute of Technology.
A key problem is the lack of documentation: for new products, the manufacturer provides tested performance values. For used components, however, the origin, condition, loads and remaining service life must first be determined at great expense.
In order for a used component to be reused, it is necessary to know where it came from, how it was used and what performance it is still capable of.
Challenges:
During the discussion, it becomes clear that circular construction is currently still largely failing due to existing structures:
• Building regulations are designed for new products, not reuse.
• Testing costs are often more expensive than using new products.
• There is a lack of uniform assessment standards.
• Public and private actors are not aligned.
Practical limits of the circular economy
• Material scarcity: Building materials are often not available in sufficient quantities for complete reuse.
• Transport costs can negate climate protection benefits if materials are transported over long distances.
• Downcycling is common: Demolition material is used in road construction, for example, instead of being reused in its original form.
Key takeaways
• Circular construction products and material passports are crucial for sustainable construction.
• The circular economy reduces waste, saves resources and lowers long-term costs.
• Cooperation between all stakeholders is key to success.
• Those who understand the concepts can actively contribute to the sustainable transformation of the construction sector.
Conclusion:
Huge opportunity, lots of hurdles
The discussion clearly shows that circular construction is central to a sustainable building transition, but currently still faces legal, technical and organisational barriers. Without new standards, reliable testing procedures and adapted legal frameworks, reuse often remains a special case.
At the same time, it is clear how great the potential is. Those who are working on standards, guidelines and assessment models today are laying the foundations for a construction industry that conserves resources, reduces emissions and truly understands buildings as material stores for the future.
Consider reuse from the outset. Plan projects so that components can be documented, tested and easily reused later. Use existing guidelines, work with experts and support the development of new standards – this will make circular construction feasible step by step rather than the exception.
Weiterführende Links:
Stuttgart 210 research project (only in German)