This is part 2 about building lightweight, insulated vaults with earthbags. Lower courses are gravel-filled bags to prevent water wicking up in the wall. Above that are standard earthbags filled with subsoil. These bags could be stabilized with lime or cement if there’s risk of flooding. Upper bags are filled with insulation and tied to rebar or bamboo arches.
The main difference between this design and the previous one for dry climates is the steep roof. Here, I’m showing a thatched roof because I’m working with a group who’s interested in building this way. Metal roofing would be a good choice for capturing roofwater and for areas where thatch isn’t available or practical. Both roofing methods protect the plastered vault from direct exposure to the elements and save on plaster work. Without a roof, the vault would be much more susceptible to roof leaks. A roof also helps prevent overheating in hot climates and mold in tropical climates.
We know earthbag domes and roundhouses are extremely popular. I predict earthbag vaults will rapidly gain in popularity as the word spreads of their speed and ease of construction. I’m almost certain they would be easier and faster to build than earthbag domes. Expect to see more on this topic in the near future.
Hello, I was wondering if the loft space in design has a structural purpose or would it work as well with out it?
Warm regards
The loft is essential for structural stability. But be advised that this plan has never been built, to my knowledge, so the idea is conceptual and unproven. I am very skeptical about the stability of earthbag vaults in general. Please keep us informed if you try to build one.
Thank you for your reply. Food for thought.
This is the idea I have in my head for a community garden shed in West Palm Beach, FL. I have to speak with the city reference a permit for a structure like this. I love this because it reduces the use of wood and may provide for a rain water catchment system. However, a) I need a roof (or system) that can withstand 140mph wind, b) something that wont contaminate the water caught for reuse in the garden and c) I’ve read that domes are not ideal for my subtropical area. This is my first time going through the “system” for permission to build and it feels a little daunting right about now.
I think I would use a round structure and conical roof with maybe 12″ overhang. Look at the grain bin roof on the Hobbit House: http://earthbagplans.wordpress.com/2011/06/23/hobbit-house-2/ That would be much easier and faster to build and gain permit acceptance.
Corrigated fiberglass panels, such as that used on greenhouses, would work also for a roof. I know of a greenhouse that has had this roof for nearly 40 years now. You do have to predrill the nailing holes and use screws or nails with rubber washers to attach it, however.
Right. You can buy commercial quality panels that are way better than the standard products.