CUBE, the world’s first carbon concrete building has been completed at the Technical University of Dresden (TU Dresden) in Germany, breaking new ground for a future-proof construction industry.

Based on a conceptual design by Henn Architecture, the 243-square-metre building is centrally located on Fritz-Foerster-Platz, at the heart of the university campus, and houses a laboratory and event spaces.

An example of architectural and structural innovation, the CUBE’s development was led by Professor Manfred Curbach and his Institute for Solid Construction at the TU Dresden in collaboration with designers, architects and experts from Henn. The experimental building is a showcase project for a larger research program on innovative building materials called ‘C3 - Carbon Concrete Composite’ funded by the German Federal Ministry of Education and Research.

Carbon concrete offers an alternative to conventional reinforced concrete, which is one of the most used building materials in the world and involves a resource-intensive and polluting production process. Carbon concrete combines high-performance concrete with specially developed carbon fibres that are processed into a fabric or rod to serve as reinforcement instead of steel rebar. Concrete is poured into a mesh made of these fibres to create carbon concrete.

According to TU Dresden, the very low use of concrete and the significant reduction in CO2 emissions compared to traditional reinforced concrete construction make carbon concrete an interesting building material, also from the perspective of sustainability and the environment.

Henn architects explain that carbon concrete is four times stronger than steel reinforced concrete, and also four times lighter due to the reduced number of structural sections. Unlike steel, carbon fibres are corrosion-proof, substantially extending the lifespan of carbon concrete structures much beyond the current 40-80 years of reinforced concrete buildings.

Buildings made with carbon concrete can also have thinner structures compared to steel reinforced concrete buildings, reducing the amount of sand and cement needed for construction. “Carbon concrete could contribute to more flexible and resource-saving construction processes, and switching to carbon concrete could reduce the CO2 emissions from construction by up to 50 per cent,” says Henn.

The fluid, textile nature of the carbon fibre yarns used in CUBE’s construction allows the ceiling and walls to be seamlessly merged into a single form as an organic continuum, instead of being two separate components. This, according to Henn, paves the way for “a future architecture in which environmentally-conscious design is paired with formal freedom and a radical rethinking of essential architectural elements”. A narrow opening in the ceiling runs diagonally across the entire structure, emphasising the building’s geometry and creating bright skylights across all interior spaces.

At the building’s inauguration in September 2022, Saxon Minister of State for Regional Development, Thomas Schmidt said, “The CUBE carbon concrete building is a big step towards a future-proof construction sector. With carbon concrete, the energy consumption of the construction industry can already be drastically reduced. Used on a large scale, it can make construction more energy-efficient, gentler on materials and more recyclable.”

While the carbon fibre used in CUBE is derived from a petroleum source and, therefore, has a high carbon footprint, the researchers are exploring ways to create carbon fibre from plant-based lignin, which is also a by-product of the paper industry.