Insulated earthbag vault with solar panels (click to enlarge)
Specifications: 263 sq. ft. interior, 74 sq. ft. sleeping loft, total 337 sq. ft. interior, one bath, Footprint: 15′-6″ x 30’
Description: As explained in one of our blog posts, earthbags are inherently unstable if they are stacked into a vault shape. The proposed design shown here resolves the stability issues. This vault building method is very strong, simple, low cost, superinsulating and extremely fast and easy to build. The shell of a small, simple vault could be built in about one week, in part because the top two-thirds of the vault is built with tubes or bags filled with lightweight insulation such as scoria or pumice (preferably nonflammable materials). These earthbag vaults are now available with a number of roof options: solar panels, metal roofing, living roof and thatch. A similar vault for arid conditions (no roof, just plaster) will be available soon.
Insulated earthbag vault floorplan (click to enlarge)
Insulated earthbag vault with living roof (click to enlarge)
Insulated earthbag vault with thatch roof (click to enlarge)
Earthbag House Plans 
Owen,
For us readers trying to understand. How does the frame work extend from the earth bag walls to support the roof and hold the insulation?
Is it wood frame with bamboo or willow rods? Steel? Very practical spaces Vaults are and they say super strong.
Just under our feet.
Did you follow the link? The drawing on our Earthbag Building Blog should be clear. Try enlarging it.
Rebar, willow poles or bamboo are pounded into the earthbags before the soil hardens too much. Cover the frame with mesh and add a coat of plaster to stiffen the frame. Then narrower bags or tubes of lightweight insulation are attached to the frame with twine. Tubes would be much faster.
One idea worth trying: Attach two ladders together at the top in an A-shape. Angle the ladders so you don’t have to step on the vault during construction. You could also try building some A-framed scaffolding with planks to stand on.
A pointed vault would be easier to build if you’re using bamboo or willow poles, and the loft has more usable space. All you would have to do is join the bamboo or willow together at the peak. This shape also simplifies roof construction.
Use rebar to build the curved vault.
The curved vault with living roof would be the most difficult and time consuming to build. It’s experimental and not recommended as a first time project. I’m just throwing it out there to show some possibilities. Plus, living roofs require regular ongoing maintenance. Be ready to climb on your roof every few days.
Dr. Geiger,
I’ve been admiring your plans for several years now, as my husband and I plan towards building our very own. Thank you for your work and bringing such knowledge to the ‘masses’!
Thank you very much.