Also commonly known as lag bolts, lag screws are some of the toughest fasteners. These extremely sturdy fasteners are usually used to connect heavy lumber or other heavy materials that are bearing an intense load.

These screws differ from normal wood, self-drilling or sheet metal screws. Compared to most ordinary screws, lag screws are massive in size. Most lag screws are at least one inch long and ¼-inch thick.

For example, wood screws are used when connecting an application with only wood materials. These wood screws boast coarse threading, but that threading does not encompass the length of the screw. Normal wood screws thread as they enter the wood, where lag screws require a hole to be drilled first. Lag screws also use a nut to add extra strength and security to help hold things together. Used for intense load applications, lag screws can support a much heavier load than the average sheet metal or wood screw.

To install lag screws, the first step is to make sure that all of the materials involved in the application are aligned. To keep the materials in place once they are aligned, use clamps to hold. Once everything is secure, drill a pilot hole using a bit with a slightly smaller diameter than the lag screw that will be used. When drilling the hole, make sure to drill all the way through the area where the screw will eventually be.

While wood screws, sheet metal screws and self-tapping screws come with a variety of head types, lag screws are only available with hex heads. To drive in a screw with a hex head, you need to use a nut driver or ratchet. Hex heads are used when a lot of torque is required. Meanwhile, other types of heads are compatible with a variety of drivers, depending on the drive. Some have slotted heads, and others have Philips heads. Torx drive screws are one exception.

Bridge Fasteners has been a leading supplier of Fasteners, nuts, bolts, stainless hardware and contractor products for over 30 years. Quality you can trust! We choose to offer a huge selection of hex head Lag Bolts because we want our customers to find exactly what they’re looking for. Hex Head Lag Bolts are available in diameters 1/4″ and up.