The silicone glass block installation system uses spacers to precisely align each glass block for you.  There is no guesswork to it.  The blocks are held in place by horizontal and vertical spacers and are bonded together with silicone.

The non-mortor system is designed for interior structures that will be no larger than 85 sq ft and framed on at least three sides. Exterior structures should be no larger than 50 sq ft and framed on all four sides.