I am planning to use earthbag construction to build a series of 3 additions onto an existing stick frame house. These are very early/rough plans as of yet. The existing single-story house is in good shape structurally, 24x32ft with a crawlspace, plus a small back porch on the north side that I plan to remove before phase 3 begins. The preliminary plan is as follows:
Phase 1 - build a 24x24ft addition on the east side. This will follow the current ridgeline of the roof but the earthen floor will be ~8" below the current floor. Essentially this will just be a single large room.
Phase 2 - Build a 24x16ft addition on the west side... then in the exiting house, we will (very carefully) tear down the west wall and the western half of the center load-bearing wall to open up the floor plan. This will also follow the current ridgeline of the roof. The new floor will need to be level with the old floor.
Phase 3 - Build a 72x16ft addition on the north side... This extension will sit lower in the landscape than the rest of the house by a fair margin so we are planning to the extend the slope of the roof down over this addition (more careful measurement is still required to verify how exactly this will work).
My wife isn't a fan of curvy walls and prefers the walls to be straight. I am concerned about the integrity of that 72ft, laser-straight wall. I assume that we'll need to include buttresses, but how many and how big are unclear to me as yet.
In addition, I am a uncertain of the best method of attaching the earthbag additions to the existing stick frame. I assume that steel strapping would likely be employed... but I haven't yet found an definitive direction on this topic.
I would love to hear about any personal experience with either of these two concerns... or if you have any recommendations for reference material that addresses these issues, I would appreciate it!
I have a great and enjoyable YouTube site to help you in your brainstorming; "My Little Homestead"This family solves every kind of earthbag problem.Additions as well in more recent "Weekly Peaks" on this channel. Good Luck and maybe these videos will turn your wife on to earthbag!
Solar Station Construction Plans by Ben Peterson -- ebook