When it comes to fastening materials together, choosing the right screw or bolt can make all the difference. One type of fastener that is particularly tough and versatile is the lag bolt, also known as a lag screw. These heavy-duty screws are often used by construction and manufacturing companies to link lumber together. Their massive size, course threading, and hex heads make them a great choice for materials that will be exposed to heavy loads.
Whether you’re a builder, carpenter, or do-it-yourselfer, there is likely to be a time when you will need lag bolts for your projects. They’re easy to use and can be found at many home improvement stores. But it’s important to know the difference between lag bolts and carriage bolt screws so you can choose the best one for your needs.
What Is a Lag Bolt?
A lag bolt is a heavy-duty screw with thick, coarse threads that only cover about two-thirds of the shaft. They are designed for wood-to-wood connections or joints and can be used in both interior and exterior applications. They are available with hex or square heads and come in a variety of lengths. Lag screws can be made of steel, stainless steel, or silicon bronze for corrosion resistance. Lag screws that will be exposed to the elements can also be hot-dipped galvanized.
While hex head lag bolts are often referred to as “bolts,” they’re technically not considered bolts because they do not have a nut. In fact, they should be referred to as screws because they are installed by turning the head of the fastener. lag bolt