Here is some information on Limestone Stucco. The first link is to an article written in 2001 describing an application in the Portland, OR area. http://www.accessmylibrary.com/coms2/su ... 345769_ITM
There appears to be one primary company that sells hydraulic lime for use as stucco in the US. That company is called Transmineral. Their website is www.transmineral.com
. They are recognized by the U.S. Green Building Council.
Someone that I spoke with at their California based office stated that on a monolithic dome, 3 coats would likely be sufficient to cover the exterior if a scratch coat of concrete was used. Based on this estimate, he figured that the cost would be 10-15% more than a conventional concrete coating.
The benefit of using Limestone Stucco is that it is less prone to cracking, is more stable, and has been used in Europe on buildings since Roman times. Some of those buildings are still standing with much of its original Limestone Stucco. This product seems ideally suited for monolithic domes which have lives potentially lasting hundreds of years.
I am interested in hearing any feedback.