This is an earthbag:

The bag is filled with a variety of options:

Insulation

Scoria (percentages vary depending on location):
Lava rock, yes the kind used for landscaping, is popular because it's one of the best insulators there is for earthbags, it is usually used for colder climates. A good rule of thumb for Scoria is that if you get more than a foot of snow in your area you probably want to use a high percentage of scoria in your earthbags (I'll go into the percentages in a bit). Do you see all the pits and crevices? That's where the air gets trapped which allows it to become a super insulator.

If you live in a cold climate you could fill bags with Scoria only and be alright. A home in Crestone, Colorado has been the proof.

Fill

Clay (20% of fill): This filler is used for 2 reasons

• It is everywhere
• It is heavy

Clay is pretty dependent on how wet it is. This is mainly because clay retains moisture and can screw up the stabilizers in the bag if it too wet and it can mess with the bags if it's too wet when it goes in.

Sand (80% of fill)
sand is another filler, it isn't as dependent on water content (because it dries out so quickly).

Stabilizers

Stabilizers are generally not needed in earthbags. Some people use them in small amounts to harden the bags around arches to allow for easier placement.
The stabilizers used most are: portland cement, lime, or emulsified asphalt.

Packing your bag

There are only about 4 ways to pack an earth bag

• mixed sand and clay fill in the entire bag
• Mixed sand, clay, and insulation in the entire bag
• Mixed sand and clay on the inside facing side of the bag with insulation on the outside facing side
• a variety of the above with a stabilizer mixed in

Types of bags

Usually people use polypropylene bags in tube form or bag form
Tube:

Bag:

How do you stack the bags to build the walls? Tune in next time for the answer.

Thanks for reading!
What do you think about earthbag houses? What do you think about alternative houses in general? I would love to hear your thoughts!

Image Sources: 12,3,4,5,6,7