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The dome uses a network of great-circles lying within the surface of the sphere (geodesics) of struts to distribute stress, so that the structure approximates a sphere in strength. The circles are placed to form triangular elements to create local triangular rigidity. Dome designs are discovered more than made. Of all known structures, a geodesic dome has the highest ratio of enclosed area to weight.
Geodesic domes are far stronger as units than the individual struts would suggest. It is common for a new dome to reach a "critical mass" during construction, shift slightly, and lift any attached scaffolding from the ground.
Geodesic domes are designed by taking a Platonic solid, such as an icosahedron, and then filling each face with a regular pattern of triangles bulged out so that their vertices lie in the surface of a sphere. The trick is that the subpattern of triangles should create "geodesics", great circles to distribute stress across the structure.
There is good reason to believe that geodesic construction can be effectively extended to any shape, although it works best in shapes that lack corners to concentrate stress.
Fuller had hoped the dome would address the emerging housing crisis - he also had hopes for his dymaxion house. The geodesic dome has also been used to provide a stable structure for industrial buildings and stadiums.
The dome was introduced to a wider audience at Expo '67 the Montreal, Canada World's Fair as part of the American Pavilion. The structure's covering later burned down, but the structure itself still stands and, under the name Biosphère, currently houses an interpretive museum about the Saint Lawrence River.
A number of people have built homes in the shape of a geodesic dome. Domes have a number of advantages.
They are very strong. The basic structure erects very quickly with a small crew, and light-weight pieces. Domes as large as fifty meters have been constructed in the wilderness from rough materials without a crane. The dome is also aerodynamic, so it loses relatively little heat to wind chill. Solar heating is possible by placing an arc of windows across the dome: the more heating needed the wider the arc should be, to encompass more of the year.
However as a housing system the dome has several problems.
On the mundane side the entirety of the funishing and fitting world is designed with flat surfaces in mind, and installing something as simple as a sofa results in a half-moon behind the sofa being wasted.
The shape leaves the vast majority of the interior surface unusable because of the sharply sloping roof lines. For example, in a 20 foot tall dome, only the bottom 8 feet or so are really usable. This leaves a large volume that must be heated, yet cannot be lived in.
Dome builders find it hard to seal domes against rain. The most effective method with a wooden dome is to shingle the dome. Another method is to use a one-piece reinforced concrete or plastic dome. Some domes have been constructed from plastic or waxed cardboard triangles that overlapped in such a way as to shed water.