Architecture

Designed by Grimshaw Architects, our two Biome buildings - the Rainforest Biome and the Mediterranean Biome - each consist of several domes joined together, and are joined in the middle by the Link building.

Inspiration

Grimshaw's starting point was the geodesic system made famous by the American architect Buckminster Fuller, who designed the Montreal Biosphere in Canada. Before Eden, Grimshaw had designed a similar structure for Waterloo International Station in London. The geodesic concept provided for least weight and maximum surface area on the curve – with strength.

Design and materials

The clay pit was still being mined when the Biomes were designed. In the face of this constantly shifting landscape, Grimshaw hit on the idea of soap bubbles. Remember blowing bubbles as a kid? They adapt to any surface they settle on. And, when two or more bubbles join, the line of the join is always exactly perpendicular (straight up and down). Basing the ‘lean-to’ Biome structures on soap bubbles was a perfect way to build on the uneven and shifting sands of the pit.

Each dome has what’s known as a hex-tri-hex space frame with two layers. The outer layer is made of hexagons (the largest is 11 metres across), plus the odd pentagon. The inner layer comprises hexagons and triangles bolted together. The steelwork weighs only slightly more than the air contained by the Biomes. The structures are more likely to blow away than down, so are tied into the foundations with ground anchors, a bit like tent pegs.

The transparent ‘windows’ in each hexagon and pentagon are made of ethylene tetra­fluoroethylene copolymer (ETFE), or ‘cling film with attitude’, as we like to call it. Each window has three layers of this incredible stuff, inflated to create a two-metre-deep pillow. Although our ETFE windows are very light (less than 1% of the equivalent area of glass) they are strong enough to take the weight of a car. What’s more, ETFE can transmit UV light, and is non-stick and self-cleaning.

• The Rainforest Biome covers about 16,000m² and is 50m high - you could fit the Tower of London inside it! 
• The Mediterranean Biome covers about 6540m² and is 30m high.
• We used 2,000, 11m-long rock anchors to stabilise the sides of the clay pit.

Jolyon Brewis of Nicholas Grimshaw and Partners designed the Core, home to our Invisible Worlds exhibition, using natural forms (biomimicry) and sustainable construction. The Core was first built in 2005 and re-imagined in 2017/18 with the new major exhibition and substantial changes to the building. This included a new Exhibitions Gallery, Café, Laboratory and two play areas in addition to a series of new art and exhibit installations. The building has also been opened up, enabling views across all floors.

Inspiration

The word 'biomimicry' describes the process of humans borrowing designs and systems from nature to create their own technology. Jolyon Brewis did exactly that when he based the architecture of our Core building on the growth blueprint of plants. He used opposing spirals mathematically based on Fibonacci’s sequence (0, 1, 1, 2, 3, 5, 8, 13, 21, 34 ...) where every number is the sum of the previous two. The spirals on a pinecone, pineapple and sunflower, like the Core roof, usually represent two consecutive numbers in this sequence.

The brief asked the architect for the building to be fit for purpose, future-proof, made with responsibly sourced materials, energy efficient, and constructed with minimal waste.

Design and materials

We worked with mechanical and electrical consultants Buro Happold to reduce the environmental impact of the building as much as possible. Innovative features include energy-efficient super-insulated walls made from recycled newspaper, flooring that was originally Heineken bottles, 'designing out' the need for a lot of concrete, photovoltaic panels on the roof provide electricity and beams made from Forest Stewardship Council-certified Red Spruce.

We're proud of the iconic architecture at Eden – and just as proud of how the buildings were made. Together with visionary architects, engineers and suppliers we've made lots of choices about materials and designs to try to keep the environmental impact of these buildings as low as possible. Here are some of the things we've tried to do: