• Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education skip experiences global resources cider press projects digital market permies.com pie forums private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nicole Alderman
  • Anne Miller
  • Pearl Sutton
  • r ranson
stewards:
  • Mike Haasl
  • paul wheaton
  • Dave Burton
master gardeners:
  • John F Dean
  • jordan barton
  • Carla Burke
  • Leigh Tate
gardeners:
  • Steve Thorn
  • Greg Martin
  • Jay Angler

How solidified should an earth bag feel after a day or two? Or, how wet should the dirt be?

 
Posts: 9
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi,
I'm in the process of building an earth bag dome, and I'm trying to figure out the right mixture of water to dirt. I've seen people say that it doesn't take much water, but what does that really mean? I've done a few bags with about 1-gallon of water in a wheelbarrow mostly full of dirt. And I did a few bags with closer to 2-gallons of water mixed with the same amount of dirt. The wetter bags were leaking some water out after a couple of hours, but when they dried, they felt as hard as rock. The less-wet bags did not leak any water out, but the next day they only felt solid from the top. If I poked the sides, they felt... slightly crumbly? soft? I'm not really sure how to describe it. Can anyone describe what the bags should feel like after they've been tamped and left for a day? Also, how long can I wait between filling the bag and tamping? It's hot, sunny, and dry here, and I'm worried the bags might dry out before I can finish an entire course and go back and tamp them.

Any advice on how to know if the bags are done properly would be helpful!

Thanks!
 
pollinator
Posts: 139
Location: Geraldton, Ontario -Zone 1b
30
hugelkultur forest garden foraging tiny house wood heat
  • Likes 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I tried to make my mixture slightly sloppy. I aimed for some seepage of water when I was tamping and they seemed pretty firm when tamping was complete, and they still are 2 years later. I was not building a dome though. It also depends on the nature of your fill material. Owen Geiger helped me to relax when it came to choosing my fill material by suggesting that if the structure I was building wasn't a dome or a 2 storey home, that I could probably use nearly anything that wasn't organic to fill the bags. I hope you'll be careful to keep the bags' sun exposure limited. It's scary how quickly they deteriorate in summer sun.  
 
pollinator
Posts: 429
Location: Victor, Montana; Zone 5b
142
hugelkultur forest garden composting toilet building rocket stoves
  • Likes 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
When I built my earthbag foundation I found that wet bags were superior to bags that had drier mixes. I think I read in an earthbag book once--don't remember which one--that the wet bags when tamped bonded the sand and clay better. This is also the experience when doing cob too. I did remember this website https://www.northernarchitecture.us/earthbag-building/the-dirt.html that talks about "weeper bags", and that they found them better to dry harder than traditional drier mixes as well. When you tamp a wet bag, they seem to not compact quite as well due to the liquid content, so you end up with a less flat bag. You want to tamp the bags the same day they are filled. I would lay down twenty bags, then tamp to use different muscles.

Depending on your weather, the bag should feel pretty hard after a few days of drying in warm weather. Obviously the cooler and higher humid the climate, the slower they will dry. All I can say is that after I finished my earthbag stemwall I accidentally backed into it with the hitch on my truck and it only ripped the bag and didn't do anything to the wall. I was using roadbase mixes from a local quarry.
 
Michael Helmersson
pollinator
Posts: 139
Location: Geraldton, Ontario -Zone 1b
30
hugelkultur forest garden foraging tiny house wood heat
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Daniel Ray wrote: I would lay down twenty bags, then tamp to use different muscles.



I tried to use different muscles but had to settle for using my own. I really felt like this was a younger man's construction technique.
 
pollinator
Posts: 1713
Location: Bendigo , Australia
109
dog gear plumbing earthworks bee building homestead
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Earth bag technology is similar to working with mudbricks, [Australia] cob in your locality.
The variables are moisture content, particle size variation and clay content.

If you grab a small handful of the mixture, squeeze it in the palm.
If water runs out its too wet.
If it breaks up its too dry
If it retains its shape and does not crack in a few days its good.

I allow at least a week in dry climates before adding layers.

 
Are you okay? You look a little big. Maybe this tiny ad will help:
19 skiddable structures microdoc - now FREE for a while
https://permies.com/t/138333/skiddable-structures-microdoc-FREE
reply
    Bookmark Topic Watch Topic
  • New Topic