11/2014 - We have installed 6mm polycarbonate on the Breathe Green Dome (shown above).
Instead of screws we used 1.25"' wide crown staples. To reduce condensation we applied
a ice and snow shield on the 2x4s, this proved to be a good match with the poly. Email us with questions. Futurespaces@msn.com
2/2012: Our newest "Breathe Green Dome" is going on 11 months and has held up very well.
Below zero temperatures and wind gusts of 50 mph and the 6 mill greenhouse film is doing just fine. 616 is 30'dia. 20'ft. high.725 the compacted fill has froze and thawed many times now with no structural damage.
Breathe Green Dome
The Crestone sphere's parameters 31 ft dia. with 2" thick modified concrete shell. The Breathe Green Domes dynamic integral frame needs no concrete. Both shells use #4 grade 60 steel welded, the sphere uses it for point load "beam pockets" and truncations "openings". The Breathe Green Domes use it for shear and dispersed load for berming 5'ft and higher, Berms less than 5'ft does not require welding.
Journal of Structural Engineering, Vol. 110, No. 1, January 1984, pp. 19-30, (doi 10.1061/(ASCE)0733-9445(1984)110:1(19)) Document type: Journal Paper Abstract:
Earth sheltered housing is a viable means of achieving superior energy performance, lower maintenance cost, and protection from extreme weather. Despite demonstrated potential for large-scale acceptance in the housing market, initial costs are currently too high to realize this market potential. At least part of the cost problem in earth sheltered construction is attributable to the common practice of using conventional, rectilinear structural systems intended primarily for lightly loaded aboveground buildings. Thin concrete dome shells are logical alternative structural forms to efficiently support relatively massive soil loads. This paper evaluates the strength and stability of 50 ft. (15 m) diameter 4 in. (102 mm) nominally thick concrete spherical domes under 3 feet (0.9 m) of saturated soil cover. Domes having diameter-to-rise ratios between two (hemispherical) and twenty are analyzed for stress levels and buckling characteristics. Neither stress levels nor stability considerations severely limit the range of feasible dome profiles, making the thin concrete dome shell an effective structural system for earth sheltered residential applications. From the perspectives of both structural and architectural design, thin concrete dome shells offer significant potential for application in earth sheltered housing.*See More Abstract by Journal of Structural Engineering.
Real results from the Black Forest "Breathe Green Dome" and data by Keith Fancher designer, fabricator and builder. Original chord factors used from the program run by *Joseph Clinton for the N.A.S.A. "Structures for future space missions" project.
Empirical load data soon available, as well as time lapse video.
Property rights Future Spaces Inc.
624 pic Crestone Sphere 2" thick modified stucco with wire mesh, uses 2 recycled lumber wraps and a continuous vapor barrier. 1' thick foam sheets are sandwiched before the vapour barrier.
248 pic Black Forest " Breathe Green Dome" 8'ft high earth berm. Integral frame/foundation supported by 4 frequency icosahedrons, see credit for chord factors*. Steel matrix design property of Future Spaces Inc. Details: Sch40 struts manufactured by: Future Spaces Inc., #4 grade 60 re-bar welded.
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