Structural building unit and method of making the same

Lightweight structural building units having a 7 day compressive strength of between 1096-3209 PSI, formed from a set solid mixture consisting essentially of about 30% to about 75% by weight Portland cement, about 1% to about 25% by weight ground expanded cellular polystyrene which has been finely ground as to yield a material wherein a single, broad and continuous size distribution of fractured cellular particles is homogeneously distributed throughout the unit to increase air entrainment capacity and provide a plurality of uniform air pockets therein, about 1% to about 35% ground cellulosic fiber, about 2% to about 15% by weight fly ash, about 1% to about 10% by weight silica fume, about 1% to about 15% by weight bentonite, about 25% to about 50% by weight water, about 0% to about 3% by weight air entrainer, about 0% to about 10% paraffin wax emulsion, and about 0% to about 15% by weight rubber emulsion wherein said paraffin wax emulsion increases the strength and reduces the susceptibility to absorb water after drying.