Enter Agriboard. As a byproduct of the wheat and rice harvest, Agriboard manufactures a pressed wheat and rice panel they call a CAF (compressed agricultural fiber) panel. Instead of burning the wheat and rice fields after their harvest, a second crop is afforded by harvesting stalks for CAF panels. The CAF panel replaces the styrofoam in the SIP panel assembly and actually has a negative carbon footprint due to the manner in which it is harvested. The panel for the Diaz Residence is 8" thick and has a R value of 24! This is about twice the R value of a 2x4 wall with batt insulation. The panel's fire rating is 2 1/2 hours and this has allowed us to build closer to the property line than a traditional 2x4 wall assembly would have permitted.
This panel also provides a viable alternative to the present straw-bale quandry in California. Straw-bale, like rammed earth, is an affordable and readily available building material that has been essentially legislated out of existence in the affordable housing market. Isn't affordable housing the place to use these relatively unprocessed low cost materials? To build with straw-bale in California today requires a steel structure to handle seismic issues. The code considers straw-bale too risky a material in and of itself. This steel work is usually too expensive for affordable housing. The place we are far more likely to see rammed earth and straw-bale these days is in higher end homes. By coupling the use of straw with conventional wood construction elements (i.e. OSB) there is a real opportunity with Agriboard to provide a structurally sound building solution here in California that is energy efficient, healthy and renewable.
This panel also provides a viable alternative to the present straw-bale quandry in California. Straw-bale, like rammed earth, is an affordable and readily available building material that has been essentially legislated out of existence in the affordable housing market. Isn't affordable housing the place to use these relatively unprocessed low cost materials? To build with straw-bale in California today requires a steel structure to handle seismic issues. The code considers straw-bale too risky a material in and of itself. This steel work is usually too expensive for affordable housing. The place we are far more likely to see rammed earth and straw-bale these days is in higher end homes. By coupling the use of straw with conventional wood construction elements (i.e. OSB) there is a real opportunity with Agriboard to provide a structurally sound building solution here in California that is energy efficient, healthy and renewable.
We are pretty excited about this project. With the approval of an "Application for Alternate Method or Material," the Diaz Residence will be the first Agriboard structure constructed in California. Its 8" thick walls will allow the use of exterior shades in the window pocket. More photos to come.