• 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 private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nicole Alderman
  • Anne Miller
  • r ranson
  • paul wheaton
  • Pearl Sutton
  • James Freyr
stewards:
  • Burra Maluca
  • Mike Haasl
  • Joylynn Hardesty
master gardeners:
  • Steve Thorn
  • Greg Martin
gardeners:
  • thomas rubino
  • Jay Angler
  • Tereza Okava

earthbags as retaining walls on a slope

 
Posts: 12
Location: UK
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi,
I'm building a small Oehler style greenhouse into a 1:3 slope and intending to use bags to hold back earth on the downward sides (both south and west slope away).  Am I right in thinking that the lateral force against these walls will be quite small as the soil and water will want to push down the slope?  It's sand and sandstone below a spades depth of topsoil and the bags are being filled with the sand and smaller stones.  It will be about 5 ft deep to support and have visqueen covering over the bags.
Thanks
 
Posts: 2
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi Steve --
We've built a few such farm buildings on our similarly steep multi-angled sloped site using earth bags over a foundation layer of a few cement bags in place. No problems structurally -- however, be careful with surface water making sure to channel it away from the upper areas of the structure. We had a 16" cyclone hit soon after build and **thank goodness** we had first started with a French drain (a.k.a. mini swale) to channel water into a moat used for animal watering.... WHEW! SO -- poultry, swine, feed stores, and sprouting areas are in tact, have survived trials and tribulations, and remain in fine form (exactly as you mention!)
Good luck with your build!
Deo, P.E.
 
gardener
Posts: 6644
Location: Arkansas - Zone 7B/8A stoney, sandy loam soil pH 6.5
1293
hugelkultur dog forest garden duck fish fungi hunting books chicken writing homestead
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Be sure to use a plumb bob so your wall is set correctly for the slope.
You also want to have a "footing", at least one bag deep below the current soil surface (similar to a house foundation) so the wall is anchored and thus won't slip down the hill from the forces of gravity.
Steeper slopes do require a set back for every layer but I don't think yours will encounter those forces enough to worry about that sort of failure over time.  
 
author
Posts: 49
Location: Silver City, NM USA
17
books solar woodworking
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

Steve Mitchell wrote:Hi,
I'm building a small Oehler style greenhouse into a 1:3 slope and intending to use bags to hold back earth on the downward sides (both south and west slope away).  Am I right in thinking that the lateral force against these walls will be quite small as the soil and water will want to push down the slope?  It's sand and sandstone below a spades depth of topsoil and the bags are being filled with the sand and smaller stones.  It will be about 5 ft deep to support and have visqueen covering over the bags.
Thanks


I would say that your plan sounds good. Sand drains very well so the hydrostatic pressure will not have a chance build up much, and sandstone is stable in its own right. If it is practical, I would incline the bag wall a bit into the berm to help with stability.
 
Steve Mitchell
Posts: 12
Location: UK
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Thanks all for the responses.  It's always good to have a sanity check from folks that know their stuff!  Good luck with the book Kelly.
Now, only a few more tons to shovel, sieve, bag....
 
Evildoers! Eat my justice! And this tiny ad's justice too!
Devious Experiments for a Truly Passive Greenhouse!
https://www.kickstarter.com/projects/paulwheaton/greenhouse-1
reply
    Bookmark Topic Watch Topic
  • New Topic