Headed Anchor Bolt Types

Headed anchor bolts are different from anchor rods or threaded anchor bolts because of the presence of a steel "cap" or head on its end. Anchor bolts are used to fasten concrete into place for a variety of projects, both commercial and residential. Anchor bolts are also used to fasten steel beams to a concrete subfloor or foundation in building architecture. The bolts are available in differing diameters and lengths, depending on your project needs.

  1. Hex Bolts

    • Hex bolts are commonly used in residential and commercial construction projects and are available up to 2.5 inches in diameter. As such, hex bolts are not manufactured to support a great deal of weight, but can still fasten a steel beam to concrete securely. Hex bolts also feature threading and are available in varying lengths.

    Square Bolts

    • Square bolts are often thicker in diameter than a hex bolt and can support heavier workloads. These bolts are identified by the thick, square-shaped head at the top of the bolt. Square bolts are commonly used in large pieces of machinery -- such as bulldozers -- and can be 2 inches or more in diameter. In freestanding structures, square bolts are also used to provide a decorative, rustic appearance for interior design in buildings.

    Timber Bolts

    • Timber bolts have been an industry standard for large-scale construction projects and machinery for decades. These bolts are identified by a large, dome-like bolt head. Used primarily for wood projects, the underside of the large, rounded, low-profile head of a timber bolt features two nubs that prevent the bolt from turning in the timber. You can also find timber bolts in older railroad ties.

    Traditional Headed Anchor Bolt

    • The traditional headed anchor bolt is used to connect steel to concrete in place of a rod or screw with a bottom nut. These bolts can be extremely thick in diameter -- often more than 3 inches thick -- and are commonly used in skyscrapers or other large architectural projects.