I've been designing and building geodesics for about four decades, and I live in a papercrete dome.
I was not able to look at your youtube because I'm out in the boonies and my connection isn't good enough for that, but I checked out the links.
That dome frame you're considering doesn't look adequate to me. The struts appear to be 1x4" and are oriented the wrong way for any strength. The hub idea isn't bad but they make no mention of the gauge of the metal. The hardware appears to be the cheap galvanized type. I think their design would be fine for camping or a wedding pavilion. It might not be good for supporting much weight.
Most greenhouses I've been in are very humid. You should keep the moisture content of papercrete below about 18% to prevent mold, not to mention that the wetter your papercrete is, the heavier it is, and the weaker it is. You'll need to consider that in your design and provide a way to dehumidify your greenhouse cover. Humidity and moisture content are not the same thing, but if you keep papercrete in a high humidity environment then the moisture content is going to go up.
Good to see a fellow domehead here. If I can help with your project (free advice) I'll be happy to.
http://starship-enterprises.net/Papercrete/index.html
spaceman
I'm glad that I see other people are thinking about the very, very same things as myself!
Here is my plan so far for a new design using papercrete. I'm wanting to use a geodesic frame the way they built using straw bales on the outside of the frame here.
http://www.youtube.com/watch?v=T2NvnhLPBVM
However I'm thinking to use the hyperadobe mesh bags to hold the papercrete as the form as I see someone else here has also thought of. Now one more extra idea I've had is to then build a second larger geodesic dome greenhouse around the whole papercrete cabin similar to what this family is doing with their cob home.
http://inthralld.com/2012/10/norwegian-geodesic-dome-residence/
I'm thinking the dome greenhouse will help deal with the sealing water issues of the papercrete while creating a nice sheltered garden area. Lastly here is the hub system I'm thinking of using so far. http://domemade.co.uk/the-hub-system/
Because the geodesic frame will help with strength I'm thinking I could go very light on the sand and even use the min on cement, what do you all think on the mix ratio's I should consider for this? Right now I'm planning for the cabin to be 300sq ft with a half loft of 150sqft and the greenhouse shelter to possibly be up to a 40ft dome.
Jackie
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