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Woman walking down steps from the Lookout in Rainforest Biome


The breathtaking sight of bubble-like Biomes nestling in a former clay mine has drawn millions of visitors from around the world. Many other examples of unique and sustainable architecture can be found across the Eden site, including the plant-inspired Core building.

Biome 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.


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.

How Eden was designed

Quote 1

Tim Smit, Eden co-founder on seeing initial Biome model

“ The moment we saw it we loved it, because it felt natural – a biological response to our needs, but forged in materials that would allow us to explore the cultivation of plants in a way never before attempted ”


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.

Facts and figures

  1. 230 miles of scaffolding

    ...was needed in building the Biomes, and got us into the the Guinness Book of Records for using the most scaffolding!
  2. 35 football pitches the size of the area that is our Outdoor Gardens, Rainforest and Mediterranean Biomes cover, which is about 13 hectares.
  3. 43 million gallons of rainwater

    ...fell in 90 days during the build.
  4. 426 tonnes of air

    ... is contained in the Rainforest Biome, and the structure only weighs 465 tonnes! (Dry air at standard temperature and pressure).

Facts and figures

  • 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.

Timelapse of Biome and Core build

Architecture of the Core building

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.


Fibonacci pattern in the centre of a sunflower

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.

Sustainable construction at Eden

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:

Green features

Computer render of hotel design

Future plans

On Eden's outer estate we have plans to build a sustainably designed eco 109-bedroom hotel, offering onsite accommodation for visitors, as well as classrooms to support our educational programmes. 

Designed by Tate Harmer, one of the UK’s leading architects for sustainability and natural environments, the striking plan features prominent timber poles, cladding the outside.