Building with earthbags is essentially building with adobe bricks without going through the lengthy process of making them. You take polypropylene sandbags, fill them with a moist mix of sand and clay, tamp them down hard and connect the layers with 4 point barbed wire. Then, you cover them over with an earthen plaster.

In reality, I didn't use polypropylene bags. Some Brasilians started a type of construction they call hyperadobe which uses mesh bags, or continuous tubing, made from the same material as the onion or potato bags in the grocery store. They don't require barbed wire, though otherwise the process is just about the same.

As I talk about in the blog posts, my design has been guided by simplicity and efficiency. More than anything, what's been most important to me is to live in a house that I myself, with no building experience whatsoever, can design, build and maintain. A natural extension of that has been the desire to live in a peaceful space. For me that means a home that's in tune with nature, thus limiting the use of imported materials for construction, in addition to those that will be needed later on, such as for heating. Please enjoy reading, ask me any questions, get inspired, and come help and learn!

Wednesday, May 11, 2011

It's snowing again?

Humanure Compost

Sample Bags

Plastic for Moisture Protection

Well, barely. But still. And thunder storms today and tonight.

Progress so far:

Before my brothers left we laid down plastic to go underneath the first course and around all of the underground layers.

I've been making test bags (above) because my first one or two cracked, though they still remained very solid and did not shatter additionally when dropped. I chalk this up to the clay drying too fast. Mesh bag mixes dry faster than the normal woven pp bag's, and since I'm in the desert...I kinda freaked out at first and then I realized it's just not a problem. I read that the same thing happens with lime stabilized bags and all you have to do is help them cure slower. So, I'm going to cover them with the plastic every day so that curing will slow. I've experimented with that a bit, placing them under a tarp, and it's helped mitigate cracking. Different moisture content gives different bags but I've tested barely any moisture to sopping wet and they all come out quite strong. If I had to guess, I'd say the moisture content I'm using--some mud will come out when tamped but not much--is about 10%. But that's a guess. It sticks together nicely when you make a ball but there isn't any excess water and it doesn't look shiny.

I'm still working on wetting methods. I've been letting it all sit together and soak for a day or two which makes it look like some really delicious chocolate cake mix. Wetting will be easier once I have the dirt in smaller piles. Luck is on my side, and one of my neighbors has a tractor that he's doing small jobs with for $45/hour. I really wanted to dig a curtain drain around my house to steer water away from the site (it will slope down to it from the house and eventually be planted on top with herbs/perennials), but it would take me a million years by hand and not worth having someone come out to do. There's other small jobs like fixing my driveway and digging basins for trees that would also get pushed back into eternity. But now that I have my neighbor Tim! I'll have him come out in the next week and do those things and move the two giant piles of dirt into smaller, more manageable ones. It will save a lot of time.

I was planning on starting to fill bags in place today. I kinda feel like I'm pushing it back because in reality I'm not going to do it today because it's cloudy, windy, rainy, and 40 degrees. That's okay, I guess. No rush. Best to start things out on the right foot. If there's a break in the weather then I will head up.

Are you wondering what happened to scoria? I was planning on getting it from Vigil's, who had quoted me a price of $35-$40 a ton plus $75-$100 for delivery, which is quite reasonable since the mine charges $36.50 a ton. When I went to finalize the order at the yard he told me a) that he would have to charge me by the yard and it would be $50/yard (it's between 1.5-2 yards/ton) and b) that this was because the price had increased without him knowing. Well, that's a ridiculously huge price change and I called the mine and the price is the same as it was two months ago so...I've talked to a friend of Jeff's, Art, who's going to go to the mine for me next Thursday and get about 10 tons. I'll use it for insulation for the floor and around the bags and probably have some extra for other projects too.

I have made exciting strides with windows. I went to Santa Fe and have bought two operable 3'x5', 3 fixed 3'x4' and a small 3'x2'. All I need is two operable 2'x3' and one operable 3'x4'. I've spent $400 so far and the 3'x5' windows I bought are very nice aluminum that they gave me at a fantastic price. I've been looking around Taos too, but deals are harder to come by here. I might go back to Santa Fe to one window shop that was closed until tomorrow, and there is also a nice glass door and a 3'x4' in Espanola I might go pick up sometime. I've got some scrap 2x6 to start making bucks.

I finally finished my compost and emptied buckets of poop for the first time. Really not bad. I guess when you decide to do something and not let it bother you, then it doesn't bother you. I'm going to ask my neighbors, who have horses, if I can clean out their hay/straw from the stables for the dry material needed for the compost pile. I used sage brush but in the long run it won't be best.

Next Thursday I have somewhere between 2-5 people coming out for a building party which would be great. I'm making sure I have everything--velcro plates, window bucks, etc.--so that building doesn't get held up on anything.


  1. Aly,

    Great start! I plan to start mine in September. Who are you getting your raschel mesh tubing from? I also want to do the composting toilet. have you seen this doc? The Ecological Dry Composting Toilet System

    I can send it to you if you want.


  2. Looking good. If you still have problems with the cracking on the bags, try adding some sand and not as much water. For your composting toilet/pile you might want to pick up some green material. Try finding a gardening service and see if they have some grass clippings you can have.

  3. Aly,

    How did your test on the red tubing Kandi sent you turn out? Did you find it able to take enough tamping so that you can get the moistened earth solid enough? Did it tear at all?


  4. Hey Tim,
    I never even bothered with the red tubing because I just didn't want to risk using it for my first building project. The bags have been great. They tamp out to about 6x16x24 and are super solid under lots of tamping. No tears. Also glad I'm doing bags because tubing would be hard alone :-)

  5. It seems to have erased two other comments here...don't know why.
    I think I have seen the toilet doc. I'm quite happy with the sawdust...for now at least.

  6. What was your cost per bag including shipping?

  7. Bags cost $.20 each. Shipping depends on how much you order. I got 2000 of them plus another type I'm not using right now and shipping cost about $100. If you get few enough that they can ship them via UPS it would probably be cheaper.