Explore making your next geodesic house.
Although extremely strong, domes react to external stresses in ways that confound traditional engineering. Some structures will retain their shape and contract evenly when stressed on the outside and some do not. For example, when a dome built at Princeton, NJ was hit by a snowplow, the stress was transmitted through the structure and popped out struts on the opposite side. The behavior of tension and compression forces in the different varieties of geodesic structures is still not well understood, so traditionally trained structural engineers may not be able to adequately predict their performance and safety.
As a housing system, the dome can have numerous drawbacks and problems:The shape of a dome house makes it difficult to conform to code requirements for placement of sewer vents and chimneys. Off-the-shelf building materials normally come in rectangular shapes. There can be considerably more scrap, left from cutting rectangles down to triangles, than with a conventional building approach, thus driving costs up. Fire escapes are problematic; codes require them for larger structures, and they are expensive. Windows conforming to code can cost anywhere from five to fifteen times as much as windows in conventional houses. Professional electrical wiring costs more because of increased labor time. However, even owner-wired situations are costly, because more materials is required with a dome versus conventional construction.
Air stratification and moisture distribution within a dome are unusual, and these conditions tend to quickly degrade wooden framing or interior paneling. Privacy is difficult to guarantee because a dome is difficult to partition satisfactorily. Sounds, smells, and even reflected light tend to be conveyed through the entire structure.
As with any sloping shape, the dome produces wall areas that can be difficult to use and leaves some peripheral floor area with restricted use due to lack of headroom. This can leave a volume needing to be heated that cannot be lived in. Circular plan shapes lack the simple modularity provided by rectangles. Furnishers and fitters usually design with flat surfaces in mind, and so installing a standard sofa (for example) results in a half-moon behind the sofa being wasted. This is best overcome by purpose-built fittings, adding to cost.
Dome builders find it hard to seal domes against rain, because of their many seams and because solar heat flexes the entire structure each day as the sun moves across the sky. The most effective waterproofing method with a wooden dome is to shingle the dome. One-piece reinforced concrete or plastic domes are also in use, and some domes have been constructed from plastic or waxed cardboard triangles that are overlapped in such a way as to shed water.
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