The System 12 consists of a Stretcher (above), a Jamb (below), a standard 12″x8″x16″ block, a bond beam 12″x8″x16″ and a 12″x8″x8″ half block. It is primarily used in commercial and institutional type buildings because these buildings typically require more structural strength that is provided not only by the larger block dimension, but the additional rebar and grout that the block can accommodate, without sacrificing thermal performance.
The System 12 adds another layer of masonry and another layer of insulation, resulting in four layers of masonry and three layers of insulation. The long and short insulation inserts shown above are also used in the System 12.
The photos above illustrate the use of 8″ Omni Corner block in conjunction with 12″ Stretcher and Jamb block. In order to maintain standard block bond which reduces block cuts, waste, material handling and increases job productivity and wall aesthetics an 8″ Corner block is used. Notice that the Corner block (right corner depicted in this illustration) cells align with the 12″ block cells. The 3.5″ “scab” piece is placed on the interior side void to complete the actual building corner. This LINK provides more information and photos of 12″ construction.