Earthbag building and rammed earth construction are very similar. Both methods utilize earth that has been tamped solid. In the case of earthbag building, polypropylene bags or tubes contain the soil and eliminate the need for expensive forms. Since they are very similar in composition, we can reasonably speculate that earthbag houses will last for a very long time – possibly thousands of years – the same as ancient rammed earth structures.
It’s worth emphasizing that earthbag building is not just bags of dirt stacked upon each other. The most common earthbag fill material is clay/aggregate soil mixture. In other words, most ordinary subsoil (mineral soil) that has enough clay to bind the sand and gravel together. When this mix is lightly moistened and tamped solid, it becomes densely compacted and extremely durable as evidenced by the following ancient structures.
More information: Historic Rammed Earth