Geodesic wonders

The geodesic domes of Cornwall’s Eden Project are a familiar sight, but less familiar perhaps is the science that makes them ideal for their purpose. A geodesic sphere is an arrangement of polygons that approximates a true sphere. A geodesic dome, therefore, is a portion of that sphere. Geodesic buildings are usually arrays of triangles that form three or five eighths of a sphere.

The triangle is a stable, difficult to deform shape, giving geodesic domes their strength. And because the surface area of a geodesic dome is only 38 per cent of that of a box shaped building with the same floor space, it is relatively cheap to heat. A geodesic dome also supports itself without the need for internal columns or load bearing walls.

Eden’s “biomes” are covered with ethylenetetrafluoroethylene. This plastic weighs less than 1 per cent of a piece of glass of the same size, and has non-stick properties, making it self-cleaning. The biomes weigh only slightly more than the mass of air that they contain.

Geodesic domes were first patented in 1954 by the American architect, engineer, poet and philosopher Buckminster Fuller. He predicted that a million geodesic domes would be built by the mid-1980s, but by the early 1990s there were only an estimated 50,000 to 300,000 worldwide.