A sci-fi future where molten lava is harvested to create low carbon building materials is the inspiration for Iceland’s national pavilion at the 2025 Venice Architecture Biennale
Volcanic activity might conjure up images of terrifying eruptions and bodies petrified in ash in the streets of Pompeii, but what if this awesome natural process could somehow be harnessed to create a limitless supply of sustainable building materials?
That’s the idea behind Lavaforming, a speculative proposal developed by architect Arnhildur Pálmadóttir and s.ap Arkitektar for Iceland’s national pavilion at the 2025 Venice Architecture Biennale.
Still a work in progress, the installation is expected to include 3D design and simulations that transport visitors through time to the year 2150 when Icelanders have worked out a way to exploit lava flows, a similar breakthrough to their first use of geothermal energy around 200 years ago.
Iceland’s exceptional geological location on a rift between two tectonic plates causes frequent seismic activity and huge lava fields, strikingly demonstrated around Grindavik last year. Lavaforming proposes using molten rock as a new form of building material, produced in sufficient quantities to construct ‘the foundations of an entire city to rise in a matter of weeks’ without harmful mining or non-renewable energy generation’.
The theme for the pavilion is also metaphorical, highlighting the current predicament faced by architecture in a world where ‘many of our current methods have been deemed obsolete or harmful in the long term’.
Pálmadóttir, who also runs the Icelandic branch of the Danish architecture and innovation company Lendager, said: ‘The architectural profession hasn’t changed much for a long time, although we are facing various challenges, we are still working in the old systems, the old economic theories and the old material processes, which have become part of the problem. We need to imagine new worlds where we look for ways to solve our problems by telling stories of the future.’
Volcanic basalt is not entirely new to construction in Iceland, having been used in the form of pumice to build light interior walls. Its denser forms have been cut into stones used to build structural walls. However, Lavaforming will focus on lava as a sustainable mono material for construction, examining how its different properties in different states and compositions can mirror the properties of mass-produced building materials. That includes employing it for load-bearing applications such as columns, beams, slabs, and walls; as a transparent material such as glass; for insulation; and even harnessing the ‘floating properties’ of pumice when dealing with buildings in areas subject to sea level rise.
According to Pálmadóttir, it’s not unrealistic that lava could one day be used on a large scale in construction: ‘One of our ideas is to dig trenches in the landscape to divert and direct lava into the shape of large walls and structures that would form a city and there is no reason why we couldn’t dig those trenches today.’
Handling molten lava with equipment is more of a challenge, she added, but once the techniques were developed ‘we could create formwork on a smaller scale’.
A fascinating meditation on a possible future, expect ‘heated’ debate from the Biennale crowd.