Buildings as carbon sinks: The Global Construction C-Sink in Practice
What if our buildings didn’t just emit CO₂ — but stored it long-term?
The Global Construction C-Sink Standard makes this possible by verifying buildings that store biogenic carbon long-term through materials like hemp, wood, cork, straw, cellulose and biochar. Carbon that was once in the atmosphere becomes part of the building itself — traceable, verifiable, and long-lasting.
In our latest video, Christoph Neururer and Andy Keel from OPENLY presents a real pilot project that shows what climate-friendly construction can look like today:
- Avoidance first — reducing CO₂-intensive components wherever possible
- High C-sink potential — hempcrete walls, cork & cellulose insulation, wood structures
- Innovation — reinforced concrete with biochar to bind additional carbon
- Designed for disassembly — a house seen as a future raw-material depot
- Healthy living — controlled ventilation without pipes
In the house of the pilot project about 350 m³ of hempcrete was used — hemp absorbs ~1.7 kg CO₂ per kg during just three months of growth. Stored safely in the building for decades.
With the first Global Construction C-Sink verification, OPENLY now:
- Shares knowledge through monthly trainings
- Acts as Global Construction C-Sink Manager, verifying biogenic carbon sinks in buildings worldwide
This is how construction becomes part of the climate solution — from day one.
Watch the video and imagine what our buildings could become.
Comments
Name: Richard Dansey
Comment Title: bamboo post and beam construction in Cambodia
Comment:
Leopa Bamboo Co is building medium size buildings in Cambodia with about 70% content of bamboo that is close to its original form, meaning that the biomass does not undergo huge transformation. We would like to register our next project as a construction C-Sink and this building will have more than 500t of bamboo in its construction in the form of bamboo poles, bamboo panel components for flooring and walls all of which have been pressure treated with borates to control insect attack and carbonized to reduce incidence of moulds. Leopa also produces bamboo biochar and this will be used in concrete works to control humidity, odor and sequester CO2. This building is designed by French architects in consultation with Leopa Bamboo and other sources and is built on a university campus that caters to furthering arts, music, dance, drama, social and cultural development and will be a fairly iconic structure in terms of its function in Cambodian society and the building materials selected. Leopa is interested to help work the processes to make the building a Construction C-Sink.
Comments
Name: Richard Dansey
Comment Title: bamboo post and beam construction in Cambodia
Comment:
Leopa Bamboo Co is building medium size buildings in Cambodia with about 70% content of bamboo that is close to its original form, meaning that the biomass does not undergo huge transformation. We would like to register our next project as a construction C-Sink and this building will have more than 500t of bamboo in its construction in the form of bamboo poles, bamboo panel components for flooring and walls all of which have been pressure treated with borates to control insect attack and carbonized to reduce incidence of moulds. Leopa also produces bamboo biochar and this will be used in concrete works to control humidity, odor and sequester CO2. This building is designed by French architects in consultation with Leopa Bamboo and other sources and is built on a university campus that caters to furthering arts, music, dance, drama, social and cultural development and will be a fairly iconic structure in terms of its function in Cambodian society and the building materials selected. Leopa is interested to help work the processes to make the building a Construction C-Sink.