CONFAST: Choosing the Right Screw for Concrete/Cement

Concrete screws securely fasten objects to concrete surfaces by directly screwing into pre-drilled holes. They provide a strong hold for medium to high load applications like attaching brackets, pipes, electrical boxes, or structural elements to concrete walls, floors, or ceilings. They are essentially a self-tapping screw designed specifically for concrete, allowing for quick and efficient installation without the need for additional anchors or plugs.

There are many considerations for choosing the proper cement screw to use for any application to ensure success. Below are some of the key factors in choosing the right screw and installation for your application.

Diameter

Cement screws commonly come in two diameters of 3/16” and 1/4”.  The measurement refers to the outside diameter of the screw, which allows the screw to be inserted through a hole in the fixture equal to the diameter of the cement screw being installed. For heavy duty projects, larger diameters such as 3/8”, 1/2″, 5/8” and 3/4″ are available.

Length

Concrete screws come in a variety of lengths from 1-1/4” long to 6”.  The Large Diameter Screws are available in lengths up to 15”, depending on the diameter. The length needed for any application usually depends on the thickness of the fixture being fastened to concrete.

Materials

Cement screws are manufactured from a variety of materials and finishes: These include zinc-plated carbon steel, galvanized, and stainless steel. The zinc-plated cement screw should be used in indoor dry applications.  When there is moisture present or in corrosive environments, galvanized or stainless steel must be used.

Head Configuration for Cement Screws

Two head styles are available: hex washer and flat countersunk.   The hex washer head utilizes a nut driver for installation and the flat countersunk requires the use of a Phillips drive.  The head style is usually dependent on the type of application.

Base Materials

These screws can be used in solid concrete, hollow precast concrete, brick, CMU, block and mortar joints.  The holding strength of the cement screw is dependent on the strength of the base material as well as on the quality of the installation.

Use

Cement screws can be removed but should not be reused in the same hole because holding values may be diminished or nonexistent.  Using the cement screw in another hole can be done if the cutting edge of the screw is able to tap threads.

You can order CONFAST, Simpson Strong-Tie and Tapcon concrete screws online 24/7 at https://www.confast.com/confast-concrete-screws/