When 68 Dutch architectural firms signed a manifesto for circular construction in 2018, it became apparent that this field is committed and eager to apply circular economy principles in designing and building for sustainable development. Nonetheless there are few available resources on commencing such a process, which is why the BNA (Dutch Association of Architects) commissioned a study on 'Designing Circularity Jointly: Circular Architecture and Construction' in 2018.

The transition to a circular economy is a quest where nobody has the correct and precise information on what inputs are required to reduce carbon emissions, ensure raw materials are processed in a circular loop and the built environment is repurposed at end of life. Designing truly circular buildings requires frameworks and insights. These are summarised in the report's eight key messages:

• circular economy is a shared quest full of complexity, obstacles and uncertainty, which is why openness, trust and courage are crucial;
• architects need more circular assignments to be able to benchmark and share experiences with each other;
• architects should play a greater role in designing buildings that can actually be built, maintained and recycled;
• collaboration across the entire value chain is necessary to map out resource flows and design in a truly circular fashion;
• regulation stimulates either renovation or newbuilds, becoming an obstacle when architects attempt to fuse old structures with new materials, linear raw materials with circular processes, and outdated standards with pioneering ones;
• despite a lot of information being available, architects find it difficult to access sustainable materials that have passed the necessary quality checks;
• the lack of clear guidelines about what is circular in the construction sector limits the adoption of corresponding principles;
• there are no easily accessible and understandable tools to guide practitioners in designing a circular structure.