Bamboo is the natural answer to the anthropogenic steel: A beautiful, structural frame that almost literally grows on trees. Used by indigenous peoples for millennia in Latin America, Africa and Asia, it is slowly being appreciated in “The West”, both for its beauty and structural properties, as well as it’s environmental benefits. 

Bamboo grows much faster than wood, maturing in less than 6 years. With proper cultivation, over 500 tonnes of bamboo can be harvested per acre over a seven-year growth cycle, whereas most wood averages less than a third of that over the same period. During its lifecycle, bamboo can sequester much more Co2 than trees; over 150 tonnes per hectare. It also takes almost half as much energy to harvest and prepare. 

Bamboo can be used much like steel for structural frames but is much more flexible and resistant to vibrations and seismic movements. It can be bent and curved, as well as joined and jointed in nearly infinite ways. The primary species used in this way is Guadua Angustifolia, a Colombian species that can reach useable heights of up to 30 metres and diameters of 20 cm, making it suitable for multi-floor construction. 

Bamboo is also a multifunctional plant; besides its structural uses, it’s early growth stages can be eaten as a vegetable, it’s roots can be used as wood replacement in furniture and flooring, and it’s upper reaches and leaves can be used as strips or fibres to create woven materials. It is a truly innovative super-material for the age of the climate crisis.

The ZERI pavilion was constructed in 2000 in Hannover, Germany for the 2000 World Expo, designed by Simon Velez and constructed by Colombian craftsmen. The structure was made almost entirely from Guadua bamboo, joined with Velez’s pioneering steel bolt and cement techniques. The roof was covered in waterproofed cement mortar and ceramic roof tiles, and the largest columns were made with Colombian aliso timber.  

The theme of the 2000 world expo was Sustainable Development, a new term at the time, and the numerous pavilions were designed to showcase materials of the future, bamboo included. However, at the time bamboo was so foreign to European architecture there were no construction standards or regulations for the material. In order to construct the pavilion, Velez and a team of Colombian craftsmen first had to build an exact replica in Colombia. This replica was then subject to physical stress tests by German engineer Klaus Steffens. These tests involved loading the mezzanine with weights of 400kg/square meter, loading the cantilevered roof spans with 650kg, and pulling the structure horizontally to simulate wind stresses, to a load of 5 tonnes. Steffens observed: 

“...the deformations are surprisingly minimal...the building gives the impression of great solidity...the execution of the work here is higher than the German standard...” 

These reports allowed construction to begin over winter of 2000 in Hannover, before being completed and opening at the World Expo, quickly becoming one of the most visited pavilions over the several months it was exhibited. 

The pavilion itself is in the shape of a 10-sided polygon, and is an open structure dominated by a massive, overhanging roof supported entirely by bamboo. The interior is fully exposed to the outside, but the vast overhangs of up to 7.5m provide very good shelter from the elements (the building had to deal with snow, rain and hail during the run up to the expo in German winter).  The mezzanine is a huge concrete slab which rests on the native wood and bamboo supports, and is accessed by two steel spiral staircases, the only metal structures of the project. 

The wooden and bamboo supports are anchored to the ground by steel ball joints sunk into individual concrete bases. This ensures that no part of the structure rots or becomes waterlogged. 

The two floored building appears squat, and this combined with several layers of large columns gives it the appearance of incredible security and stability. However, this does not preclude it from beauty. The natural materials and craftsmanship are the highlights of the structure. Velez has used every part of the bamboo cane, not just the strong middle part of the cane, but also the curved bottom and rhizome to create grand sweeping arches and curves. The roof seems to float above the comparatively thin columns, supported by hundreds of smaller, hidden pieces of bamboo. The dark red of the steel, the yellows and browns of the bamboo and aliso wood, and the orange of the terracotta tiles all create a warm, welcoming colour palette which makes the building glow in photographs taken in its native Colombia. 

Velez was tasked with showing that bamboo could stand among the materials of the future, he achieved that by showing its versatility, strength, and above all else it’s beauty.

What is it to be an architect during the climate crisis? Is it to be mindful of the embodied energy in materials? To use passive solutions to reduce heat loss? To insulate, retrofit, re-use and recycle? I think it means all and any of these things. 

 The vast majority of modern architecture is a monoculture of steel, concrete and glass. All these materials are extremely environmentally costly, and this is without mentioning the mountains of petroleum-derived products which infiltrate every aspect of construction. These materials are not widely recycled in the construction industry, and they lead to a form of architecture and thinking not suited to their home climates, buildings that simply do not function correctly in their context.  

This cannot be continued by the next generation of architects. New materials must be embraced, as well as traditional and vernacular architectural styles and materials that are molded to their specific place and climate. This necessitates a centering of minority and indigenous architects and craftsmen, as well as a complete abolition of the neo-colonialist, extractive, and unethical forms of labour and material harvesting. 

Nature must be embraced as the primary client for all architects, and buildings must be seen not as an object, but as a system that interrelates on a fundamental level with nature and the environment. This must be an abolition of the unsustainable monoculture in favour of variety: more materials, more architects, more craftsmen, more styles and vernaculars. Being an architect in the Anthropocene means exploring the vast array of different forms of practice throughout the world and opening to nature. It is exciting, new and demanding. It demands: Anything but this.