![Wegwijzerborden op een campus.](https://www.buas.nl/sites/default/files/styles/header_slider_default/public/2026-04/Materials-min.jpg?h=4362216e&itok=ymZVqFLI) # Circularity

As a Climate-Positive Organisation, BUas works towards a sustainable campus and organisation through a range of topics, one of which is circularity.



 

 

 

 Circularity consists of two interconnected elements: material inflow and material outflow.

- **Material inflow** concerns what we bring onto campus: the building materials used in our buildings and the goods and services we procure. It covers the full life cycle of those materials, from how they are produced and sourced to how circular and demountable they are. Our aim is to create maximum positive ecological and environmental impact through our procurement practices, while also weighing the social and economic dimensions of our procurement decisions.
- **Material outflow** concerns what leaves campus as waste: how much we produce, how well we separate it and how much we recover as raw material rather than disposing of it.

These two topics are two sides of the same problem: what we buy determines what we ultimately throw away. By tackling both together, we follow the logic of the circular economy: limit what comes in and recover as much as possible of what goes out.

    ![people getting food at catering](https://www.buas.nl/sites/default/files/styles/4_3_groot_wysiwyg/public/2026-09/2026_industry_network_event-26-1-1.jpg?h=507e3564&itok=E3bVCn2B) 

Our current focus is establishing baselines for both topics. For inflow, [Haskoning](https://www.haskoning.nl/) carried out a CO₂ emissions analysis across all procurement categories in 2023. This showed that food and beverages alone account for 65% of our procurement-related emissions. In 2026, we are focusing on supplier engagement and setting category-specific KPIs for CO₂ emissions, biodiversity impact, waste reduction and social value. For outflow, in 2026 we are carrying out a waste audit together with students to understand our current waste volumes, separation rates and contamination levels on campus. We also want to raise awareness of waste separation within our community. We do not yet have all the data we need and are building our measurement systems as we go.

For the procurement of goods and services, we want to be a frontrunner. For building materials and waste management, we want to lead by example. Both are serious ambitions, and both require structural change across procurement, facility services, catering and campus behaviour.

 

 

 





 

 

 ### Contact

For questions about sustainability-related matters at BUas, please contact <sustainability@buas.nl>



 

 

### Documents

[Material inflow - definition &amp; action plan](https://www.buas.nl/cpo-material-inflow-def-doc)

[Material outflow - definition &amp; action plan](https://www.buas.nl/cpo-waste-def-doc)

 

  

 

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