We resume our monthly meetings at Whole Foods Market in 2011 by welcoming Joe Alderman from PCM South. Joe contacted me after running across something I had said about one of compressed earth blocks' best attributes, that of being host to a phase change material. In the case of compressed earth block (and likewise adobe, rammed earth, and other earthen construction) the phase change material is water. The earthen material absorbs moisture out of the air overnight and gives it up to evaporation in the heat of the next day. The act of evaporation, phase changing from liquid to gas, requires heat to occur, and draws that heat from the surrounding spaces. Swamp coolers operate in much the same way.
Joe Alderman has a patented process of adding phase change material, in this case specific salts, to cellulose insulation to be used in standard wood stud construction in wall cavities, ceilings, or immediately under roof decking. Instead of fluxing between liquid and gas like water does, the salts flux between solid and liquid phases. All the detail you can burn your brain cells on can be found on Joe Alterman's website, PCM South. So if you are intrigued with the cooling attributes of phase change materials and you don't happen to be fortunate to live in a compressed earth block home (yet), all is not lost. You can benefit from phase change materials in your conventionally-built home. Come to the meeting on the 25th to learn more.