Earth bags for insulation?

I have never heard of earth bags before (oooo all the new fun things to learn on permies. )

I was wondering if I were to stack a 4' wall along the outside of my house if it would provide some insulation.

Not really. Earthbags are good thermal mass but quite poor insulators, which somewhat limits how practical they are in cold climates.

It is possible to fill bags with scoria (lava rock) or perhaps perlite for an insulative bag-building method. You can have load bearing insulated bags, infill bags, split bags with part earth /part insulation, double walls of earth and insulation bags, etc etc...there are some earthbag building forums out there with more info...

Fill bags with packing peanuts?

I wondered about that as a non-loadbearing insulating outer wall below grade (ie stacked against earthbags). I would worry about it stacked up as an exterior wall above grade as was talked about in the OP. I would worry about fire getting into something like that... about it burning fast with a really deadly smoke...I don't know, but I would want to do some homework to put my mind at ease before going ahead.

Hi Kari. Our plan this year upon returning to the south is a combination of earth bag subterranean with about 2-4 feet above ground utilizing straw bale construction. The hole in the earth should be approximately 6 to 8 feet deep and the interior and floor lined with earth bags and pvc pipe running between floor rows for geothermal radiant heat & cooling and the floor layered in 2-4 inches of re-bar reinforced concrete.

Albeit heat isn't a huge concern on a cool evening the PVC will be tapped into a copper section of tube wrapped around the barrel portion of a rocket stove mass heater. This will provide adequate heating of the water controlled by a 12V zone valve and pump in conjunction with the mass of the stove to create a comfortable temperature with the existing earth / soil temperature.

Now cooling is a concern where we have purchased out land the temps easily range to 100+ in the summer so the top portion above ground 2-4 feet will be a straw bale design utilizing reinforced fiberglass stucco as a finish.

Habitat for humanity did several studies on this type of construction before implementing it on Indian reservations in the north. The insulation value (although contested in number) fell just short of a polystyrene home (Basically #2 from the top) with a calculated R-Value of 58. The second test was safety and a map gad torch placed on a straw bale coated with chicken wire and 1-2" of reinforced stucco lasted two hours under direct heat before the flame penetrated to the straw. (Obviously it lasted much longer than a conventional stick frame house.

I have built straw bale sheds and storage units in the desert areas of Utah and Moab, UT has a active program for building these homes in high heat areas and they perform excellent.

Lastly our plan is to cover the roof portion with a reinforced beam system similar to a hobbit house (Round design with load bearing in the center and finish the same way with bales and stucco. The final touch will be implementing a live roof to both further insulate from the sun and to be used as a garden (Hence the possible 4" high to simulate a raised bed for easy maintenance of the garden).

This design in my humble opinion offers protection from the heat, the low profile avoids easy detection in a SHTF scenario as well as significantly more stable in a storm / hurricane or natural disaster situation. The Earth provides a constant temperature and geothermal warming or cooling of water can also be easily tied into the build as well. We also intent to do install a outlaw well (DYI Self Drilled) inside the structure and it will eliminating 10+ feet from the drill (Not much but what the heck) 50-75 feet we need to go to hit the local aquifer.

The idea is to keep the water source hidden and protected as well and be serviceable from inside without nosey inspectors or neighbors learning of its existence. We intend to duplicate the hobbit house because its just me and my wife and we require very little open space so for us this will be affordable and sustainable for little to no cash investment. (I have been in construction from a family craft for 30+ years) but I am confident with a little research and some advice here on this board you could duplicate this plan and adapt it to be larger as you feel the need.

Our long term goal is to duplicate the one hobbit house with a subterranean walkway to another identical large room between to be used as a large under ground Aquaponics grow room.

Even if one or two of these ideas can help you I am glad to share any info as well as I am sure other will as well. Good luck with the build Earth bag is good in a lot of situations like others have stated but do remember it has no great insulation value. Mass yes / insulation no... so unless you are building below ground once the mass is heated or cooled the room temperature is very hard to stabilize.

Mark Phillips wrote:
" We also intent to to install an outlaw well (DYI Self Drilled) inside the structure..."

Noble effort.. hiding the well from snooping revenuers! However, a thought. I seem to recall that bringing a well up inside a dwelling might not be a good idea since it also allows a path for radon gas to enter the dwelling. Something to check out before proceeding. Other than that, I wish you well. I have similar thoughts of mostly subterranean dwellings using earth bags and John Hait thermal conditioning concepts.

I've heard of using earthbags filled with other stuff as insulation - such as shredded straw packed between rafters and even bags filled with rice hulls. Even wondered if bags filled with wood chips would work. Clearly they couldn't be structural like dirt filled earth bags, but stacked against a structural wall should be good insulation.

Would be easy to combine with (dirt-filled) earth bag construction by half-filling bags with the lighter 'airy' material, and interleaving the unfilled half of the bag between courses of dirt filled bags - resulting in a double wall tightly tied together. Hopefully such a wall would be stable enough on the outside (insulated side) to take a stucco or cob render after being wrapped in chicken wire.

Earthbags aren't a great insulator but they can be used as such by adding materials that create air pockets inside them, like volcanic rock. However, earthbags provide terrific thermal mass properties. Simple thermal dynamics state that heat travels from warm spaces to cooler spaces. While you may want to shade earthbag structures in summer months, they can absorb heat from the sun and release it into your house on cold winter nights. When used in conjunction with passive solar heating and cooling you'll almost never need to use heat or air conditioning.

Before using earthbags on your home I highly recommend distinguishing the differences between thermal mass and insulation to see which is best suited for you and your family

Mark Philips : Lets get the well out of the way, Your local County agent for the soil and water district should be able to tell you if Radon is, or is not a potential problem !
It goes without saying that you should have your water tested! ( for everything) Being self aware of what could be released from a Fracking well site with a cracked well
casing ( industry estimates are 6% of all wells drilled will have problems with its well casing !) You want to know whats there, and have valid third party certification!

If you feel competent to run a vertical well drilling rig, go for it, I have a friend who got taken in by a well driller who sold him an old worn out rig, Trust but verify !

Outside of the noise older hammer-drill type rigs make you should be able to drill very close to your house and be out of sight! Basements are very unpopular right now,
but an outside trap door type cellar entrance is a good way to hide the well and pump, and will allow you to setup above a well that must have more work, if you have a
house sitting on top of your Well Casing you are probably screwed !

I have lots of respect for Habitat for Humanity, and love their RE-Stores ! Could you please find and share more information on their Stucco over straw bale design, its
funny, but one region doesn't always talk to an other !

Planning on getting hot water off of a Rocket Mass Heater is more than a little problematic, what safe guards do you have for a loss of Electrical power and Someone run-
ning the Rocket Mass Heater ! The sudden flashing to steam of a plumbing component has the potential to equal what happened at the Boston Marathon, only with more
severe 2nd and 3rd degree burns over the whole body !

For the Good of the Craft ! BE SAFE, Keep warm ! As always, your comments and questions are solicited, and are Welcome ! PYRO - MAGICALLY Big AL !