Concrete screws, also called anchor screws, are designed for quick, safe, secure fastening for a variety of jobs in concrete, brick and cinder block/masonry. They are an externally threaded, hardened screw with a double lead, consisting of alternating raised and lowered threads with notches cut into the threads, and a diamond-shaped, nail type point. Concrete screws eliminate the need for an anchor when used in light and medium duty applications. When used in concrete, concrete screws can be removed and re-driven into the same hole. Special carbide bits are recommended for driving the screws into masonry. Concrete anchor screws provide self-threading action and maximum holding power for anchoring the following to masonry: electrical junction boxes, wooden beams, plywood, exterior insulation, metal flashing, expansion joints, duct straps, gutters, fixtures, and thresholds. These screws are available in two different head styles: flat head and hex head. Flat head screws have a phillips drive style, while the hex head can be a slotted or unslotted indented hex head style.
Concrete Screw Finishes
Concrete screws are most commonly supplied with a blue polymer finish, however they are also available at AFT plain, zinc plated, with a PermaSeal environmental coating, or with a Ruspert corrosion resistant coating. The benefits of PermaSeal and Ruspet coatings is that they are available in a variety of colors to match your application. Stainless steel options are also available.
Installing Concrete Screws
Concrete screws should be installed a minimum of ten anchor diameters between each other, and the hole should be a depth equal to the required embedment plus ½”. Pre-drilled holes are required before the screw can tap threads. The hole size is critical and the proper carbide drill bit should be used to ensure that the proper tolerances are met. For example, a 3/16” x 1-1/4” screw requires a 5/32” x 3-1/2” drill bit.
As a supplier of concrete anchor screws, AFT offers a wide range of sizes, styles, and brands, including Dewalt, Strong Point and Power-Con. Please search our product selection online or contact us with questions or assistance. Our knowledgeable staff is available to help!