There are two (2) distinct types of BLOCK JOIST^® Systems. Both are constructed in place.

The first type may be untopped. Load Tables 1 and 3 apply to this untopped system.

The second type requires a 3000 psi concrete topping 2" thick. load tables 2 and 4 apply to this type.

7" deep steel BLOCK JOIST^® and 8" blocks, either 16" or 24", for spans up to 20 feet are the major components for the vast majority of uses. A liquid 2.5:1 (masonry sand and Portland cement) grout fills the spaces left between the blocks. The joist is easily handled. It is very stable and weighs less than 4.5 pounds per linear foot. A 20' joist can be comfortably handled by two workers, one if necessary. All components can be carried by hand to their final location.

Unlike most slow manual work, the BLOCK JOIST^® System can be constructed quickly, and therefore economically. The reasons for this speed are the high quality of the components and the simplicity of the work. When set on level bearings, the BLOCK JOIST^®, made to applicable Steel Joist Institute Specs, are automatically level. When the ASTM C90 blocks are set on the joists, they provide an automatically level top surface. When poured from only two or three locations along the joist, the grout is so liquid it visibly fills the trough containing the joist. The same grout, spread with a wide squeegee, fills the coarse surface texture of the blocks and leaves a flat, smooth top surface. When covered, the wet blocks cure the grout.

For small areas, gloves, a spirit level, a wide squeegee, and a five gallon bucket are the only tools needed by the worker constructing the slab. The grout is easily mixed in a motorized mixer, or with a hoe in a mortar box. For larger areas and several workers, the grout may be delivered by ready-mix truck and pumped. All of the work is performed on top of the slab being constructed.

No shoring, no forming, no welding, no crane, and no specialized equipment needed. "It is fun!" a builder said. "I love the BLOCK JOIST^® System," a masonry contractor said.

Note: If a fire rating is required, contact the BLOCK JOIST Co., LLc. The blocks and the Load Tables are different for the fire rated BLOCK JOIST Systems.