Monday, June 28, 2010

earthbag construction

notes for earthbag construction of a 10 by 12 structure as a prototype for a larger structure.

If you are wondering what I'm talking about google "earthbag construction"

Earthbag home prototype.

Dimensions internal: 10'*12*12 Before roof.
Dimensions external 11'* 13'*12 “ “ “ “

an 11 ft length is 5 bags and a 13 is 6 so each layer uses 22 bags.

Facts and assumptions: bags are 14”*26” with an assumed thickness when filled of 3” or
1092 cu in or .63 cu ft.

Walls will require 1056 bags and 4608 ft of barbed wire.

Basement is 13'*11'*-6' (6' deep hole) will provide 858 cu ft of fill material. Or enough for 858/.63 or 1350+ bags. Enough for the walls.

Sloping the roof. Based on my readings it is not recommended to exceed an overhang of more than ¼ of the width of the bag or with these bags no more than 3.5 inches per layer. I'm nervous and live in an earthquake prone area so I'll go for 2' per layer for the roof. The roof will require 54 layers and will be approx 13.5 feet tall for an above ground height of 20 ft. losing a bag per side for every 13 layers or,

6*5 for the first 13 layers (286 bags) , 5*4 for the next(234), 4*3 (182), 3*2(130), 2*1 (78) At this point I'll change orientation of the bags by turning the next layer by 90% and capping it off.

Takes 910 .bags.


Bags :1966. Note: no windows or doors in this calculation so the actual number will be smaller.
2000 bags cost $580 delivered
Barbed wire 6 rolls. $630 delivered. Roll is 1320'

1250 cu ft of clean fill..

Still figuring out how much stucco/cement/papercrete to skin it and the cost of application

approx internal space:

Basement 10'*12'*6 or 120 sq ft or 720 cu ft
main floor 10'*12'*8' 120sq' or 960 cu' (note: walls begin to slope at 6' so this calc is over.)
loft approx 7'*9".
assuming floors at 6" high loft peak is 20-9=11 ft