Rammed Earth is a very effective means of doing this, if you have the right forms and the right soil consistency. Too much sand, and not enough clay or silt, for instance, and you are going to have issues, but rammed earth can be added to the growing list in this thread. ...ala William B
Maybe rammed earth walls might be a more environmentally sound and cheaper option
Alternatives include earthbags, gabions, blocks of compressed tires,soil cement,slip form stone walls.
I like Dale's gabion cage ideas. I have often thought, after being introduced to the idea from Dale, that this is the cheapest and fastest way to build structural mass, and it gives a nice outer layer with which to adhere cob or stucco. In regards to creating dense thermal mass with it, I was thinking that a person could fill the gabions a little slower, mallet packing dirt material around the large stones, or mortaring it with cob, around the outer edges of the gabion especially. This would ensure that there was more density to gain and retain thermal mass into it's center, rather than just a rock basket, with a lot of air spaces between stones.
Thick gabion walls offer the benefits of thermal mass,
This doesn't have to be the case, but you should keep in mind, Jeremy, that in order to build an earthship, or almost any alternative structure, you are going to need help. Extra labor, volunteer or otherwise, is essential to such endeavors, or it's potentially going to bury you.
I've only seen one finished earth ship. It has been a colossal failure, in energy wasted, and in using up a major chunk of a man's life.
Doug Kalmer wrote:
...Slipforming is an old building method where wooden forms are set up wall thickness apart. A flat-faced stone is placed against a form, and concrete is poured in behind the stone, forming a wall with embedded stones facing out. Once the concrete has set up, another layer of forms is placed on top, and the process is repeated.
Now, with two (or more) layers of forms up and concrete set up, you can remove the bottom forms and leapfrog them up the wall, thus greatly conserving form lumber, as you work your way up and along the wall.
Most stones are not very large and heavy. Flat-faced stones do not have to be very thick to cover a fair amount of wall. The heaviest piece of wood in my house is easily heavier than the heaviest stone.
Bryant RedHawk wrote:I believe that if you start replacing the thick tires (soil thickness not the tire thickness) then you are moving away from earthship design as I understand it.
As far as the reduction of issues, yes it would work better but it is not serving the function of re-purposing that the earthship was designed to do.
As far as the thermal mass, it would be able to have more thermal energy stored, thicker is better, black it the right color for thermal mass storage.
My understanding of the RMH is that the heat comes through the exaust pipe (flue) so I don't think you could run one RMH to heat an entire floor area, perhaps two to three would be needed.
John C Daley wrote:OK, I have to ask, what are CMU's?
Marcus Billings wrote:Roberto has made some great points. I think if it works for you, and your situation, do whichever. If you choose to go "pure" earth ship, that's great, but don't be afraid of the concrete if it works best for your situation. No one has all the right answers and to enslave your ideas and dreams through some else's preconception is a mistake. Concrete worked great for the Romans, and for me personally there are just some things that work better when they are made of concrete. Footings, posts, erosion control and basically anything you want to stay put for a long time are great uses for concrete, and it holds thermal mass well. I think it's important to remember to be practical. If prepping and setting the tires takes X amount of time, and concrete installation equals one quarter of X, I would go concrete because that is time you could be using to create other parts of the earth ship, or whatever you would call it. (and if anyone wishes to admonish me about the evils of concrete, save your breath)
There's no study for longevity in this situation, but my guess is that the concrete will last longer without needing repair as well.
I'd equate it to preparing land in a key-line system. Most people that do it aren't using horses, they're using tractors, because the speed at it which it can be done mitigates the carbon being used to accomplish the task. Berms and swales can be created and planted quickly and most folks see it as a good trade off. The carbon they'll sequester in foliage the first year or two will offset the petro that was burned to modify the land. And I agree with this concept: we need to get this planet planted, and quickly, so a little carbon used in the right places can go a long way.
If the end product behaves as you predict and saves you time, money, and carbon foot-print over the long haul, it's probably a sensible move. Just my thoughts.
Lynne Cim wrote:Straw bales! I love that our walls were sourced from right down the road, came "pre-compacted", and were able to stack to make 16 feet of ceiling height.
I think we paid less than $1500 (12 years ago) for all the bales which built all the exterior walls in our 1200 SF house.
The R value is great and the house breathes fresh air + we know there is nothing toxic used.