Depending upon application and cost, Slaglite, Slaglite II, Ko-Lite and Haydite block are manufactured in a variety of sizes to offer a wide product selection for the architect, builder or mason contractor.


The Slaglite masonry unit is a durable, mid-weight all purpose block that has been manufactured for over thirty years and has been a cornerstone of excellence. This unit is typically a fine textured, sharp edged mid-weight unit with good layability and uniform light gray color.

Slaglite II

The Slaglite II masonry unit is a heavier weight block that is durable and has the same visible characteristics of the Slaglite unit. It is manufactured with a minimum of lightweight aggregate and is more economical. Because of its nature, this block has a lower shrinkage coefficient than the Slaglite or Haydite masonry units.


The 12×8-16 Ko-Lite Masonry Unit is manufactured from expanded shale and cold slag aggregates. This unit is approximately three pounds heavier than Haydite and three pounds lighter than the all purpose Slaglite unit. It is considered a mid-lightweight that is more economical than Haydite and still provides good layability and production. This unit would be a good choice for foundation work or commercial work where cost and production is important.


The Haydite masonry unit, manufactured from lightweight expanded shale aggregates, is the lightest and most functional load bearing block available, It is typically a fine textured sharp edged unit that is slightly darker gray in color than mid-weight block. This unit, which has great layability, also has excellent thermal and fire resistance characteristics. It has been accepted by both BOCA and Underwriters Laboratory as the industry standard for fire resistance and is also outstanding in sound absorption. Where weight, production, fire resistance and sound absorption are important, the Haydite masonry unit is an excellent choice.

Water Repellent

Also available on special order are Water Repellent block. These units are manufactured with an integral water proofing additive and color with or without score. However to achieve the most satisfactory results, these units are manufactured from heavy dense raw materials and must be layed with full head and bed joints. To deter water penetration to its fullest, it is essential the same water repellent additive be used in the mortar.

*Most blocks are available in both Haydite and Slaglite.


Concrete Block Styles and Sizes