A fastener that has self-drilling properties is known as a screw. When a screw is installed into a surface, the threads lodged on the surface of a screw dig through the surface material. They fix themselves into it very strongly and make it harder to remove. They also allow easy insertion into a material so that anyone can install them.

There are many types of stainless steel screws that are designed specifically for different materials. One of the most popular applications of a screw is joining two pieces of wood together, and the screw used for this purpose is known as a lag screw.

What Is a Lag Screw?

A lag screw is also known as a coach screw. Lag screws are large and made up of metal, with mostly ahead in the shape of a hexagon. The hexagonal head makes the screw very optimal for use in high-stress conditions. They are available in various sizes for different uses, but the most popular ones come in the size of 1 to 3 inches with a thickness of 0.25 at least.

While other screws are much more petite and lightweight, lag screws, because of their size, are way stronger and reliable. For this reason, they are a sound choice for woodworking and other applications where multiple things are expected to be joined together. This is also where the name ‘Lag screws'' originates from because they were traditionally used to secure two wooden lags together.

The Benefits

There are many benefits of using lag screws depending on the application. But these screws are a good choice because they can sustain enormous amounts of pressure and strain. For this reason, manufacturing and construction companies use lag screws. The reason behind providing better performance than other screws is because of the bigger size, girth, and design.

Apart from their strength and durability, lag screws are long-lasting as well. A lag screw has a carbon-rich steel core which makes it strong. The galvanized zinc exterior makes it rust-resistant and even more strong and long-lasting. Because of the galvanized zinc layer, it becomes almost impossible for any oxygen or moisture to reach the core and make it weak. This is why these screws can last for decades while also providing stability and durability.

Lag Screws in Softwoods

When using for more delicate and smaller pieces, it is wiser to use smaller-sized screws for a better and more secure fit. If the density of the screw is heavier than the object, there is a high risk of the object’s getting damaged and inability to sustain the weight. So, for the overall better health of the object, it is advisable to use the required size of screws.

Lag Screws in Hardwoods

Installing the lag screws in the wood can be quite a challenging task. If you have nut setter bits, then you are good to go. But if you don’t, it is difficult to install the screws as they might now be a good fit for the socket they are being used in. This is where small washers come in handy because you can just use them to make the screw a snug fit for the socket and make your job easier.


A lag screw is a large, heavy, durable screw that can be employed for woodworking because of its functions. They have a hexagonal head which gives them a higher level of performance and the galvanized zinc coating makes them resistant to moisture and oxygen. They are the most preferred because, despite their heavy size and durability, they are easy to use and install.