The Advantages of Using a Concrete Screw

Concrete screws, also known as masonry screws, are used to anchor a variety of items to masonry. They require a pre-drilled hole and should always be installed using a carbide drill bit to ensure proper tolerances.

This type of anchor is ideal when a mechanical interlock is required and for permanent attachments in concrete, hollow brick or block. They come in a range of lengths and approval ratings including ETA, fire and seismic.

Keying

Often referred to as a tapcon, the concrete screw is ideal for fastening items like shelf brackets, towel bars, rake and shovel brackets, pipe and conduit retainers, shower doors, and other lightweight fixtures to concrete or masonry. The concrete screw, or tapcon, works by tapping threads into base materials such as concrete, hollow brick, cinder block and Portland cement plaster (stucco).

Unlike other masonry screws, concrete screws require no pre-drilling. They are designed with a gimlet point and alternating high and low threads that cut as they are screwed into place, allowing for self-threading and maximum holding power.

Simply drill a hole to the proper size with a hammer drill and masonry bit (drilling depth should match anchor size). Insert the anchor, tap in place with a hammer and then tighten with a wrench. For extra strength, you can cut lengthwise strips of wire solder and push them alongside the anchor as it is being installed.

Threads

Another significant problem with conventional concrete screws is that they tend to collapse or damage the threads when driven into hard aggregate concrete. This is caused by the relatively thin and sharp thread convolutions of the screw as measured in its axial dimension at the root of the thread.

This invention provides a self-tapping concrete screw which may be readily tapped into a pre-drilled bore in a concrete or other masonry structure without risk of shearing the screw or damaging the screw's threads. The invention also provides a screw which can be driven into a concrete or other masonry structure with substantially improved pull-out strength for a given depth of penetration.

The screw is provided with a serrated cutting thread which begins at a blunt leading end and extends toward the head. The thread crest diameter is substantially uniform from the frusto-conical portion to a point spaced about one inch from the screw shank. The screw is also preferably made from a material which is resistant to hydrogen embrittlement, since this can cause the failure of conventional concrete screws in some applications.

Length

For fastening applications in concrete, brick or block, a concrete screw (also known as a Tapcon) is the ideal option. They are easy to install and provide high load values without the need for hammering!

Unlike other screw anchors, concrete screws have serrated cutting threads which cut their way through the base material to provide a strong grip. They require a smaller drill bit to create a pilot hole before they can be driven into place, and must be installed with care.

When choosing a length, it's important to keep in mind the minimum embedment requirements as well as the maximum. A pilot hole should be drilled at least 1/4 inch deeper than the length of the concrete screw to ensure that when the screw cuts its own threads, there is room for any dust to fall away from the gap. Flathead Tapcons are measured from their overall length, while hex headed concrete screws are sized from under the head as it will remain outside of the fixture being fastened.

Embedment

A concrete screw, sometimes called a masonry screw, is ideal for light-duty fastening to concrete and brick. Also known as Tapcon screws, they have a special thread that cuts into the material to create a strong hold.

To use concrete screws, first drill a hole with the right size drill bit. It is important to keep the drill bits clean, as debris can cause the screw to bind and break.

Next, insert the concrete screw into the hole. It is a good idea to use a washer, which can help with the installation and ensure that the screw is properly aligned.

Some contractors like to pre-screw the concrete screw into a wood plug, but this is not necessary. A concrete screw will create a tight, secure fastening with a proper amount of preload. This is the best way to prevent loosening or movement of the screw during the life of the project. The preload is defined as the screw’s capacity to resist deformation by the material of the bolted joint.