I am looking into the possibility of building with concrete block (do not know how different from cinder block). I have enjoyed a book by Jim Eggert on "Low Cost Earth Shelters". It also details "Construction with Surface Bonding" which was published by USDA. I found this on the internet. You can dry stack the blocks and then apply to the side walls a thin coating of this surface bonding. Makes possible installation by unskilled labor.