Engineer-approved TJI/Earthbag System
I’ve been reading about the building boom going on in Wyoming and the Dakotas from all the oil and gas exploration. There’s currently a severe shortage of affordable housing in the area. But the climate is very harsh and so conventional earthbag building is not so practical. We’re always searching for faster, easier, lower cost, better ways of building. This opportunity got me thinking about how to optimize code-approved earthbag building in extremely cold climates with short building seasons.
Precision Structural Engineering, Inc. is willing to approve an innovative building system that uses vertical TJIs (engineered joists) on piers and scoria-filled earthbags on rubble trench between piers. This is similar to the EcoBeam system, where earthbags are used as fill between posts. Differences include: scoria-filled bags create an insulated foundation; tubes are recommended instead of bags to speed construction; earthbag upper walls (area above where moisture can cause problems) could be filled with perlite, vermiculite or other material for higher R-value. Plans must be adapted for each area to meet wind and seismic loads.
This building method would include the first code-approved insulated earthbag foundation.
Piers cost less and use less concrete than typical foundations.
Walls could be thinner than typical earthbag walls to conserve space. (12” is suggested. Perlite = R-3 x 12” = R-36, which is double or triple most wood framed walls.)
Siding could be added to speed construction.
Insulated TJI or wood box bond beam speeds construction.
Contact Precision Structural Engineering, Inc. for details
[Between Bill Taha and sub-consultants, they carry licenses in 48 states nationwide. They have also completed projects in 14 countries internationally and counting. PSE, Inc. developed the first engineer-approved earthbag system that can be widely adapted to most any design. See http://earthbagbuilding.wordpress.com/2010/12/04/reinforced-earthbag-specifications/]