Structural Lightweight Concrete is a versatile building material typically with unit weights from 90 to 125 pounds per cubic foot and compressive strengths from 2,500 psi to more than 8,000 psi. Since it is generally 20% to 40% lighter than normalweight concrete, a structure’s dead load can be reduced, its foundation costs lowered, and it’s concrete and rebar lessened. Structural lightweight concrete also resists fire better than normalweight concrete because of its lower thermal conductivity and its lower coefficient of thermal expansion.
The secret to high quality lightweight structural concrete lies in the aggregate used to produce the mix. Norlite is a ceramic material produced by expanding and vitrifying select shales, in a rotary kiln. The process produces a high quality ceramic aggregate that is structurally strong, durable, environmentally inert, light in weight, and highly insulative. It is a natural, non-toxic, absorptive aggregate that is dimensionally stable and will not degrade over time. The use of Norlite and other quality components in a mix will provide a concrete that offers all of the advantages derived from being light in weight while not sacrificing performance of the concrete.