CalEarth SuperAdobe

Product Description

SuperAdobe is a rammed earth building system developed by CalEarth that uses long or short sandbags (filled with moistened earth) and arranges them in layers or long coils to build shelters or landscaping retaining walls. Strands of barbed wire are placed between each layer of sandbag to act as both mortar and reinforcement. The system is free to use for non-commercial construction and the bags are available for purchase.

Target Users (Target Impact Group)

Distributors / Implementing Organizations

CalEarth has participated in many relief initiatives and their system has been implemented by several organizations including Small Earth and the Heliotrope Foundation's Konbit Shelter.

Manufacturing/Building Method

Sandbags are made to order. Barbed wire, shovels, tampers, soil, and water are other materials that must be obtained elsewhere. To build a SuperAdobe wall system, users should lay earth-filled sandbags down and tamp each course. Between each layer, strands of barbed wire are placed to serve as a mortar-substitute and provide tensile reinforcement in the wall.

Intellectural Property Type

Patent Protected

User Provision Model

Users can obtain SuperAdobe bags by ordering them online and having them shipped anywhere in the United States. For projects needing shipment outside of the US they provide a list of earth bag manufacturers from around the world. Users can also obtain training (campus or online) from CalEarth in earthbag construction.

Distributions to Date Status

Unknown

Design Specifications

Bags come in widths of 14, 16, 18, or 20 inches and lengths of 250, 500, and 1000 yard rolls. The earth bags are synthetic, low UV (ultra-violet) resistant and degradable. The manufacturer recommends using four-point, two strand, galvanized barbed wire between each bag course to add tensile strength. Also recommended is the use of stabilizers such as cement, lime, or asphalt emulsion mixed into the earth for more permanent structures. To protect SuperAdobe structures from erosion, plaster or exterior finishes should be used. Each layer of bag should be tamped and coiled when stacking the wall. Applicable SuperAdobe structures include structural arches, domes, vaults, rectilinear shapes, landscaping and infrastructure elements (dams, cisterns, roads, bridges, and shoreline stabilizers).

Technical Support

CalEarth offers workshops for learning how to build using the SuperAdobe system both at their campus and online. They offer introductory classes to SuperAdobe and an entire curriculum for various prices.

Replacement Components

It is unlikely that repairs are needed, however bags can be purchased in small lengths should sections of a structure need to be rebuilt.

Lifecycle

Though the full lifespan is unknown, some of the earliest earth-bag structures that CalEarth and alumni constructed have been standing for more than 10 years.

Manufacturer Specified Performance Parameters

Manufacturer performance targets include structural safety, fire-proofing and insulation, flood resistance, and ease of building.

Vetted Performance Status

CalEarth claims that performance has been vetted for structural integrity and fire resistance. Academic research has tested the quality of ventilation, lighting and insulation.

Safety

CalEarth describes the Superadobe system as being a very safe method of construction because there is no need for large equipment. Workers may be exposed to regular dangers of a construction site that include working at heights and with sharp tools and materials (barbed wire, saw to cut windows, etc.). If constructed using CalEarth's recommendations, users should not have to use expensive equipment or perform any heavy lifting. Otherwise, users should take precaution when lifting large quantities of earth to prevent injuries associated with heavy lifting.

Complementary Technical Systems

CalEarth cites Midwest Permaculture as a educational organization that offers resources for earthbag building and a Permaculture Design Certification (PDC) upon completion of their curriculum.

Academic Research and References

Canadell, Samuel, Comprehensive design method for earthbag and super adobe structures. Materials & Design, 2016. 96: p. 270-82

Zhao, Ziling., An Energy Efficient Building System Using Natural Resources–Superadobe System Research. Procedia Engineering, 2015. 121 p. 1179-85

Kamal, Razia, and Md Saifur Rahman. A study on feasibility of super adobe technology–an energy efficient building system using natural resources in Bangladesh. IOP Conference Series: Earth and Environmental Science, vol. 143, no. 1, p. 012043. IOP Publishing, 2018.

Lushnikova, Nataliya. Approaches to Teaching Building Materials and Technologies for Energy-Efficient Sustainable Construction. Budownictwo i Architektura 15, no. 3 (2016): 53-62.

Lopez Gomez, Marco A., Nuria L. Pérez, Maria de las Nieves González García, and Alfonso C. Escamilla. 2019. CONSTRUCTION OF A SUPERADOBE DOME. engrXiv. March 14, 2019. Universidad Politécnica de Madrid.

Compliance with regulations

The blueprints available for purchase come with structural calculations that can be submitted to a building department for permission to build. The SuperAdobe houses are accepted for permits in several states including California which has the highest requirements in the US for resistance to earthquakes. In 2021, SuperAdobe was evaluated by the International Code Council and received ICC compliance.

Other Information

There are international workshops for interested individuals outside of the United States. In 2004, SuperAdobe technology was awarded the Aga Khan Award for Architecture.