Building Process

Building an earthbag home is a straightforward process. There are certainly nuances involved, but the principle is pretty basic: stack up the dirtbags.

Artificial forms are made ahead of time to replicate the presence of windows and doors. By creating these you can lay the earthbags around the planned gap as needed. As you can see by the picture to the right an arch can be used to close off rounded windows and doors. I chose to show this process because I really like the looked of rounded off windows and doors. You can see from the picture up top that traditional flooring approaches can be used, merely placing the framing into the earthbag wall.

Between each course of earthbags is layed down two lines of 4-point barbed wire. This acts to hold the bags together so they don't slip at all during the laying process. As mentioned before the first few courses are made up of gravel (or in the case of the picture it looks like they are just using bags of cement). Stacked atop that would be bags of soil.

The secret to getting a perfect circle made is to use a compass. A tall pole is driven into the center of the roundhouse. From there a chain or rope is made that is the length of the desired diameter of the roundhouse. As each course is layed you check with the compass chain to ensure that each layer is exactly round and in line with the previous.

There are a number of ways to attach a traditional roof to an earthbag roundhouse. What seems the most secure (in my mind) is to affix a concrete bond beam to the top of the wall. A concrete form is made around the circumference of the earthbag wall. Large pieces of rebar are inserted through the form and into the earthbags (securing the form to the earthbags). Then the cement is poured. From there traditional roofing practices can be used.

Finally some kind of protective layer needs to put over the earthbags. You can use stucco, concrete, or any number of plasters. From what I've read a lime based plaster would be the best to use as it seems to hold up to the elements well.