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Geodesic Dome

Geodesic Dome

The Geodesic Dome was invented by Buckminster Fuller in the late 1940s. It was designed as an efficient building structure that addressed many of the housing issues related to traditional buildings. The geodesic dome is considered to be a very efficient means of enclosing space. Fuller's invention went relatively unnoticed in 1951 when he began to apply for patents. Recently, however, standardized designs and manufacturing techniques have led to an increase in the number of "dome kits" that are offered by a variety of manufacturers and distributors. There are close to 50,000 geodesic domes in existence today.

A geodesic dome consists of a network of triangles that are joined together to create a roughly spherical surface. If a sufficiently large number of triangles are used, the geodesic dome approximates a true sphere. Furthermore, different sized triangles allow the geodesic dome to be divided symmetrically by 31 different great circles. A great circle is the largest circle that can be drawn around a sphere. On Earth, for example, the equator represents the only latitude line that is a great circle. On the other hand, all longitude lines are great circles. Because of these properties of symmetry, geodesic domes get their name from the Latin word geodesic, meaning "Earth-dividing".

The benefits of a geodesic dome structure can be realized by examining the properties of a sphere. For example, a sphere represents a shape that has the highest volume to surface area ratio. This means that material costs can be minimized without sacrificing interior space. Furthermore, a half-sphere (the shape used for most residential domes) allows for a maximum amount of floor space for a given surface area. Compared with a traditional 1500 square foot home, a 1500 square foot geodesic structure (with a 23-foot high ceiling) uses almost 20% less building materials. Since they have less surface area, geodesic domes are able to reduce heating costs by as much as 50% when compared with traditional buildings. Because the spherical shape also tends to absorb the most external light, additional energy savings can be realized by reducing the need for artificial lighting.

Geodesic domes are extremely stable structures. This is partly due to the fact the triangles, which are naturally stable polygons, are used throughout. This is one of the reasons triangles are so popular in homes, buildings, and bridges. In a geodesic dome, these triangles eliminate the need to include load-bearing walls without sacrificing stability. In addition, its curved surface offers a natural layer of protection from high winds and other environmental stresses. Geodesic domes have been used in such places as Antarctica where wind speeds can reach 200 miles per hour.

You can find out more about Buckminster Fuller and geodesic domes from the Public Broadcasting Association .