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Geodesic Dome

A geodesic dome is a spherical building in which the supporting structure is a lattice of interconnecting tetrahedrons (a pyramid with three sides and a base) and octahedrons (an eight sided figure—two pyramids with four sides and a base, placed base to base). The first contemporary geodesic dome on record is Walter Bauersfeld's, who realized the utility of projecting the constellations on the inner surface of an icosasphere, Omnimax-style, thereby creating a breakthrough planetarium in Jena, Germany, in 1922. However, the geodesic dome common today was invented and patented by R. Buckminster Fuller in 1947.

Geodesic domes are fractional parts of complete geodesic spheres. Actual structures range from less than 5%-100% (a full sphere). The Spaceship Earth Pavilion constructed by Tishman Construction for AT&T at Walt Disney World's EPCOT is the best-known example of a full sphere.

Several physical and mathematical ideas factor into building a geodesic dome. For example, a convexly curved surface is stronger than a flat one, most materials are stronger in tension than in compression, and the most rigid structure is a triangle. A hemisphere encloses the most space with the least amount of material while the tetrahedron encloses the least volume with the most surface. These principles make geodesic domes the strongest, lightest, most energy efficient buildings ever devised. Structural patterns of geodesic domes vary in complexity. Some domes have been built using simple interconnecting triangles as a support structure while others have icosahedrons as their supporting structure. An icosahedron is the geometric form having the greatest number of identical and symmetrical faces—it has 20 faces, 12 vertices, and 30 edges. The more complex the structure is, the stronger it is.

Geodesic spheres and domes come in various frequencies. The frequency of a dome relates to the number of smaller triangles into which it is subdivided. A high frequency dome has more triangular components and is more smoothly curved and sphere-like.

Geodesic dome structures are used as private residences, commercial buildings, places of worship, schools, sports arenas, theaters, and vacation homes. Dome homes can be found in all 50 of the United States. They can be found in many places throughout the world such as China, Africa, Europe, and the Antarctic. Some notable geodesic domes are the Climatron, a climate controlled botanical garden in St. Louis, Missouri (1960), the Houston Astrodome (1965), and the dome for the American pavilion at Expo '67 in Montreal. Humans A geodesic radardome at Lowther Hill Civil Aviation Authority Radar Station in Scotland. The dome is made of fiber-glass which, unlike concrete, is transparent to radio waves. Photograph by John Heseltine. National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission.
have been living in domes such as mud huts, igloos, and thatch huts for millions of years.

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