They describe lava as “molten concrete without the cement” — once cooled, it becomes basalt, a strong, durable building material. Since the extreme heat makes it impossible for humans to handle directly, the concept relies on robots that would collect lava from active flows and feed it into 3D-printing systems with controlled cooling to shape it into building components.

Beyond novelty, the idea targets cement and concrete production, a major source of CO₂ emissions — especially relevant for Iceland’s ongoing volcanic activity. The architects say the technology likely won’t be viable until around 2150, but the concept already represented Iceland at the 2025 Venice Architecture Biennale.

If realised, volcanic eruptions could shift from being purely disasters to potential raw-material windfalls for construction.