A concrete nail is a type of mechanical fastener used to secure objects into masonry and other hard and brittle materials. Nailing into masonry requires the right type of nail, a good quality hammer, and some technique. Concrete nails are often used in building construction and in home improvement projects, such as finishing a basement. A concrete nail is a special fastener and is different than a common iron nail.
A concrete nail has a head on one end, and a cylindrical shaft that tapers to a sharp point at its other end, to help engage the nail by penetrating into the objects being fastened. The cylindrical portion of the nail is known as the shank. The head of a concrete nail, which has a round shape, provides a positive mechanical stop, and a surface for a hammer to be used to pound the nail into the material. Concrete nails are also available without a head.
The shank is what gives concrete nails a very firm holding strength. The shank is usually short, thick, and often ribbed to provide piercing and clenching strength. There are a variety of shank types available, including smooth, ring, twisted, and twilled. The ribbed shanks provide surfaces that help to grip the concrete and reduce the chances that the nail will loosen and come out over time.
Concrete nails are most often used with a special power tool, known as a nail driver, which provides a strong hammering action to allow penetration of concrete. The tool generates a strong pounding action along the axis of the nail to drive it into the concrete in a single blow. Using a nail driver increases the ability of the nail to penetrate the concrete quickly and with less effort, and produces stronger and more accurate mechanical connections.
A concrete nail can also be hammered manually. It usually requires several blows with the hammer to fully sink the nail, and may result in reduced gripping strength and holding power. Pilot holes, which are slightly smaller than the diameter of the nail, are usually drilled into the concrete before manually hammering the nail. Pilot holes help to maintain the accuracy of the hole, and reduce the force needed to pound the nail in.
Concrete nails come in different diameters, lengths, and shank types to meet a wide variety of applications. A concrete nail is normally harder than a common iron nail. Galvanized concrete nails are the most common type, and are widely used. These are made of high-quality carbon steel and are zinc-plated to provide strength and corrosion resistance.