Here’s some background info on domes.
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History
The earliest domes were probably roofed primitive huts and consisted of bent-over branches plastered with mud. Another primitive form, called a beehive dome, is constructed of concentric rings of stones and has a conical shape. Ancient examples have been found in the tombs of Mycenae (Ancient Greece or the East Mediterranean Bronze Age civilisation pre 500 B.C.) and can also still be seen in the folk architecture of Sicily. Although there is evidence of widespread knowledge of the dome, its early use was apparently restricted to small structures built of mud brick.
It was the Romans who first fully realized the architectural potentials of the dome, culminating in the 2nd Century A.D. Later this continued with Byzantine builders at Constantinople A.D. 532–37 and Islamic architectural use of domes. During the Italian Renaissance many churches were covered by masonry dome structures.
The dome in modern architecture utilizes such construction materials as reinforced and thin-shell concrete, glass and steel, and plastic. An innovative contemporary approach to the form is the geodesic dome. These are low-cost, geometrically determined hemispherical forms as promoted by the architect Richard Buckminster Fuller (see notes, below) for low cost housing. Among the best-known examples of geodesic domes are the United States Pavilion at Montreal’s Expo 67, Biosphere II, an experimental recreation of the ecosystem in Arizona and the Eden project in Cornwall.
Reasons for using domes
The geodesic dome has an aesthetic quality, a beautiful shape which can be used for a variety of purposes such as temporary accommodation or an extra room outside the house, summerhouses, workshops, storage space, children’s playhouse, a meeting room, spare bedroom, study area, sauna, meditation retreat, travelling tent, etc. The possibilities are endless. Some people also use domes in Britain as permanent living accommodation. The Tinkers Bubble Community in Somerset for instance, have some domes which are cosy, insulated and heated and lived in all year. In summer the sides can be rolled up for extra ventilation.
Its minimal use of non-renewable materials and its ability to be self built without employing ‘experts’ means its process of building and use has a very low environmental impact.
It is very cheap to build. Using ones own labour saves costs. As a guideline it takes 1 person roughly 4 (7 hour) days, i.e. 28 (wo)man hours, to build from start to finish. The material costs are also very low: assuming that most of the tools are already owned or available. The actual cost of pipe, oil, pins and bolts can be as low as £15-20 for a 4.25 metre / 14 ft diameter dome. Cotton canvas covering can be anything from £40-150 second hand up to £700 for new fitted material.
The dome is more or less a half sphere shape. In terms of eco-design, the surface area ratio to volume is lowest in a circular building; therefore, it is the most efficient design for reducing heat loss.
Geodesic structures have shown themselves to endure through severe storms and earthquakes, due to the strength of their design. Geodesic domes have been used successfully for Antarctica radar towers with up to 200mph winds for over 25 years.
The nature of the spherical design provides strength because the stress is shared evenly by all the points of the structure. The dome shape allows environmental stress such as movement from an earthquake or wind or stress from snow loading to be evenly distributed throughout the structure. The geometry of the triangle offers additional strength to the dome shape.