What does a C-sink manager do?
Experts from a wide range of disciplines work at Openly. Reason enough to bring our colleagues in front of the curtain at irregular intervals and introduce their areas of work. This time, we put a few questions to Dr. Christoph Neururer, who heads up the "C-sink certification" department at Openly.
Dr. Christoph Neururer, CO2 Certification, Life Cycle Assessment & EU Working Groups
Question: Openly has very successfully implemented the Valley Widnau pilot project, with which you are presenting your "new building" concept. Can you explain the most important key data?
CN: With the apartment building with 19 residential units, we were able to impressively demonstrate the dual effect of "sustainable construction". On the one hand, the considerable - around 50 percent - CO2 savings through the use of biogenic materials. On the other hand, the building is also a carbon sink and stores 552 tons of CO2, which is thus removed from the atmosphere in the long term.
Can CO2 sinks be included in an environmental balance sheet to improve the overall balance of a construction project?
CN: This is possible, although the handling varies from country to country. In Switzerland, carbon sinks can be integrated into the SIA 2032 standard. In Germany, the equivalent would be the DGNB label, which assesses the overall performance of a construction or conversion project. In the SIA's accounting logic, Valley Widnau achieves 1.94 kg CO2 per m2 GFA, while the DGNB's figure is even +/- zero. If you think Europe-wide like we do, it would of course be nice if the calculations had the same specifications.
What professional experience and qualifications do you have for the position of C-Sink Manager? What motivates you about the job?
CN: I am a graduate engineer and studied at the University of Natural Resources and Life Sciences in Vienna. I completed my doctorate in 2014 in the field of "Life cycle assessments in the building sector at an early planning stage". So I've been working on this topic for a very long time. After my studies, I was able to accompany major projects for over 11 years. My motivation is and has always been to "rethink construction" and reduce CO2 emissions associated with the construction and operation of real estate. At Openly, I bring my experience from the numerous large-scale projects, and I am convinced that we need new approaches in terms of materials and processes in order to change the construction sector in a sustainable way.
What are the tasks of a C-sink manager?
CN: The C-Sink Manager plays a central role in construction projects that realize carbon sinks through the use of biomass such as biochar or wood. He ensures that the materials are properly tracked, tested and certified to enable removal certificates. His tasks include inspecting the property for compliance with standards, checking compliance with defined specifications and checking the quality and quantity of biogenic raw materials. In addition, the C-Sink Manager prepares all the necessary data for the C-Sink register and submits it for registration. Through comprehensive project monitoring, he ensures both sustainability standards and effective carbon sequestration. Finally, he determines the size of a C-sink in a building.
What is the ideal collaboration between the client and C-Sink Managers?
CN: Clear framework conditions are essential for successful collaboration. A detailed concept that defines goals and expectations forms the basis. In addition, a regular exchange between the client and specialist planner is crucial, and it is an advantage if the C-Sink Manager is involved in the construction project as early as possible. Personally, I look for the solution that makes the most sense for the building owner and client, even if this is not always the one with which we realize the largest C-sink.
In your opinion, how has the interest and demand for buildings made from biogenic materials developed in recent years?
CN: In recent years, interest in buildings made from biogenic materials has increased significantly. This can also be seen in large-volume residential construction, where the demand for timber buildings and hybrid timber buildings has increased significantly. For a sustainable transformation of the construction industry, it is crucial that pilot projects can be scaled up. In addition - similar to the introduction of energy efficiency standards - clear guidelines or incentives must be created to promote positive developments. A solid framework, comparable to the energy standards, plays a central role in the sound assessment of buildings - the prerequisite for the development of a functioning market for biogenic construction.
C-Sink managers ensure that buildings such as the Openly Valley Widnau pilot project can bind up to 552 tons of CO2 in the long term.
Webinar series
milton.earth, OPENY and Carbon Standards International are joining forces in a series of webinars to shed light on the various aspects of buildings as carbon sinks and their certification.
Market & Monetization Deep Dive
Wednesday, June 18, 2025 - 3:00 p.m. - 4:00 p.m.
With Claudia Feurstein, milton.earth (by Openly)
All about market mechanisms and monetization opportunities.
Certification Deep Dive
Wednesday, August 13, 2025 - 3:00 p.m. - 4:00 p.m.
With Dr. Christoph Neururer
Details about registration, documentation and certification of new projects.