The Venice Architecture Biennale is branching out this year, but has it gone too far?

Architecture is in crisis. Construction is responsible for nearly 40 per cent of global carbon emissions, but architects can hardly afford to stop designing buildings. The curatorial team for the 19th Venice Architecture Biennale, led by Carlo Ratti, invited architects and designers to propose solutions to this problem in an open call; more than 280 projects by 750 participants made the final cut for this year’s show, titled ‘Intelligens. Artificial. Natural. Collective.’ At such a staggering scale, the exhibition mostly amplifies rather than resolves the field’s central dilemma, with planet-saving projects sitting awkwardly alongside noisy high-tech polluters. Like its half-baked title, the show never feels thoroughly cooked. I wish I could say the same for the rest of us.

The opening display makes the stakes plain. In the Arsenale, a sweltering room full of air-conditioning units, suspended over oil-dark vats of water, fills up with the heat produced while they keep the rest of the Arsenale cool. Produced by Sonia Seneviratne, David Bresch and Daniel A. Barber with Cittadellarte and Transsolar, it’s an unusually tactile installation for a show that is otherwise full of the turgid wall texts and printed digital renderings typical of most architecture exhibitions.

Next up is a high wall whose steep incline matches the 20th-century rate of population growth, courtesy of Beatriz Colomina, Roberto Kolter, Patricia Urquiola, Geoffrey West, and Mark Wigley. We’re told that the ‘other side’ of this hill, a mess of chewed-up foam that resembles a bacterial culture, represents a pending mass-casualty event, sparked by climate change, pandemics or other catastrophes. To survive, humans must learn from nature. In a wall text, Ratti describes architecture as a mechanism of survival, asking: ‘Can we make a building as smart as a tree?’

Exhibition view of ‘Picoplanktonics’ at the Canadian Pavilion at the Venice Architecture Biennale 2025. Photo: Luca Capuano; courtesy La Biennale di Venezia

Some responses seem drolly literal: treehouses for humans designed by Peter Pichler and tiny shelters for bats by Studio Gang. Others seem more immediately useful, like a flood-resistant adaptation to shelters for Rohingya refugees in Bangladesh by Marina Tabassum Architects. In dozens of projects, roof gardens and brick walls abound. Many of these rely on technology as ancient as Babylon, which may not be a bad thing.

There are intriguing experiments with new materials, too, mostly displayed in a crowded maze of clay-coloured scrims. Banana fibres are used as roof thatch (Zichen Xu and Kevin Mastro), seagrass as packaging (Vessel), hemp as a binder in concrete (Humanitas360). These impressive scientific advances do little to diminish the dystopian atmosphere in the third section of the Arsenale, where robots nearly match humans in number. One flails helplessly inside a hanging steel cage, while a nearby pair bang on steel drums. Meanwhile, two Bhutanese wood-carvers work on an elaborate door lintel before assembled passers-by, while a robotic arm designed by Bjarke Ingels blithely sweeps the sawdust away. It looks disconcertingly like a taskmaster to these two human labourers doubling as live entertainment. (Around this point, the AI summaries at the bottom of each text panel stopped feeling like a handy time-saver and more like a form of narrative control.)

In fact, the niftiest bit of science isn’t in the Arsenale. At the Canadian Pavilion in the Giardini, Living Room Collective is growing architectural segments from vats of cyanobacteria. They look horrifyingly like Cthulhu, but suck carbon out of the air in order to harden themselves. By contrast, many of the other national pavilions celebrate indigenous building practices, from the floating wood and straw houses of Lake Titicaca (Peru) to the earthen homes of Cappadocia (Turkey). The chinampas, or floating gardens, of Xochimilco are a fragrant highlight at the Mexican Pavilion, where they appear well adapted to green Venice.

View of ‘Necto’ by SO-IL, Mariana Popescu, TheGreenEyl and Riley Watts at the Venice Architecture Biennale 2025. Photo: Marco Zorzanello; courtesy La Biennale di Venezia

Curators Luciana Saboia, Eder Alencar and Matheus Seco have used the renovation of the Brazilian Pavilion as an opportunity to study both modern and vernacular approaches to challenging environments, from drainage systems in the steep favelas of Salvador to elevated walkways in the flood-prone Amazon River delta. Axonometric drawings have been printed on a wooden table and panels suspended from steel cables and white granite counterweights. The display is simple but ingenious, much like the case studies themselves.

The British Pavilion, meanwhile, considers its position on a diagonal axis linking London to Kenya’s Great Rift Valley. For ‘Geology of Britannic Repair’, a beaded curtain made of agricultural waste has been draped over the building’s terracotta exterior, invoking Maasai dwellings. The core of the pavilion inverts spaces linked to British colonial extraction and turns them into canopies. The Palm House at Kew Gardens, where tropical plants from colonial expeditions were stockpiled, is rendered at reduced scale in wood, so it resembles the upturned hull of a ship, after which it was originally modelled. The interior of a slave cave in Kenya, scanned and reconstructed with bamboo lattice across the ceiling, resembles a nest for swallows. These poetic gestures are accompanied by a regrettably hollow one: a room full of concrete fragments and tools that ‘takes inspiration from Gazans’ reappropriation of rubble’ without acknowledging Israel’s role in destroying the Strip – or Britain’s complicity, besides a reference to the Balfour Declaration of 1917. The UK’s refusal to prevent arms from being exported to Israel goes unmentioned.

Such wilful blindness undermines an otherwise admirable project. Ratti’s exhibition is similarly unable to reconcile its many sustainable contributions with those that promise to generate only more waste. The final chapter of the main exhibition features designs for colonies in outer space: Clouds Architecture Office, for instance, has proposed a compound submerged underwater in a Martian crater, while IVAAIU City suggests building new data centres on the moon. Such outlandish ideas come across almost like late-night Elon Musk tweets. If the show is serious about confronting the climate crisis, it seems counter-productive to propose leaving the planet behind.

Exhibition view of ‘GBR: Geology of Britannic Repair’ at the British Pavilion at the Venice Architecture Biennale 2025. Photo: Marco Zorzanello; courtesy La Biennale di Venezia

The 19th edition of the Venice Architecture Biennale runs until 23 November.