David C White

Mr. Stadnyk,  How do I get in touch with you?

David White

Seems to me it ought to work.  I want to try it. Has anyone else tried it?  I figure on chipping it, soaking in water and then doing the boric acid treatment.

DAvid White
South Carolina

Glad I found this thread.  I have been wanting to build with rammed earth for some time and now have the opportunity.  But I'm being told that rammed earth is not great in our warm climate and that we need to increase its r-value.   So I am looking at adding hemp or bamboo to the mix to do that.  Using lime as stabilizer - not cement.  If I can't make it load bearing then I will add cement stabilized pillars ever so often and infill with the hemp/earth.  If necessary i will add a hempcrete skin to the outside.  


For the second story I was thinking squared off logs stacked using the butt and pass method.  Log buildings have the same problem as rammed earth with low r value so might add the hempcrete to that as well.  

Then I got to thinking of not squaring the logs.  stacking poles using the butt and pass method - giving it time to dry and shrink and then adding hempcrete to the inside and outside.  I am looking for the solid construction - not the look of the earth or logs though I know that it can be beautiful.  I might side the second story with tin if I want fire resistance or wood siding if I want the look.

I'm also messing with biochar for agricultural purposes but curious about its use in building.  Ithaka institute in Europe is using it in a plaster.  Also adds insulation value.

If anyone can comment on the insulative value of adding fiber to rammed earth I would be grateful.

David White
Darlington SC

Is there a hydraulic tamper that would run off a tractor?  That is what I was counting on.

David White

Rammed earth as we do it today doesn't pass muster with modern energy codes.  Builders are faced with adding a layer of insulation to get permitted.  I don't want to give up on the idea of rammed earth.  Can I add enough biochar to increase insulation enough to get the job done?  I found the following in one paper online so I guess don't go over 10%.

Biochar was used as a replacement for cement and aggregate in cementitious composites and as an addition in wood polypropylene composites and plasters. The biochar dosages ranged from 0.5% to 40%; in most composites, the addition of biochar increased strength and reduced thermal conductivity and the bulk density of fresh mortars. Also, biochar dosages of 0.5–2% decreased, while dosages of 10–40% increased water absorption and penetration on cementitious composites.

So maybe I build a couple small walls, one with and one without biochar.  using a heat lamp would be a reasonable way to test the conductive/insulative quality of the walls?

David
South Carolina

Rammed earth as we do it today doesn't pass muster with modern energy codes.  Builders are faced with adding a layer of insulation to get permitted.  I don't want to give up on the idea of rammed earth.  Can I add enough biochar to increase insulation enough to get the job done?  I found the following in one paper online so I guess don't go over 10%.

Biochar was used as a replacement for cement and aggregate in cementitious composites and as an addition in wood polypropylene composites and plasters. The biochar dosages ranged from 0.5% to 40%; in most composites, the addition of biochar increased strength and reduced thermal conductivity and the bulk density of fresh mortars. Also, biochar dosages of 0.5–2% decreased, while dosages of 10–40% increased water absorption and penetration on cementitious composites.

Thanks for any advice.
David
South Carolina