Home Power Tools

How to Buy Lag Screws

10 min read


Lag Screws for DIYers Table

A lag screw is an incredibly useful tool for every home DIYer.

Whether it is used for simple tasks or complicated projects, they are essential for any home handyman or woman.

Here’s a rundown of why you should consider having one in your toolkit:

Lag Screws Benefits
Easily driven into hard materials Drills easily into wood, metal, plastics, and more
High-torque performance Can handle heavier loads and will not lose grip over time
Reliable durability Made from rust-resistant steel and will last for years
Cost-effective Affordable, easy to find, and used again and again

Lag screws are powerful and sturdy, yet surprisingly inexpensive.

With a variety of sizes and styles, you can find one that is just right for you.

Whether you are fixing a leaky sink pipe or constructing a new fence, lag screws are essential for every DIYer.

Defining Lag Screws

Lag screws, also known as lag bolts, are bulky screws used to securely fasten two pieces of wood together.

They have very large, smooth shanks with threads that are designed to make installation easier.

Typically, lag screws have a hexagonal head, although some have a round head.

Lag screws also feature coarse threads that are capable of easily penetrating any type of wood.

Special types of lag screws are also available, such as multi-start screws and self-cutting screws.

Whichever type you select, lag screws are an essential part of any woodworking project.

Our Goal

Our goal is to help you purchase the best lag screws for your do-it-yourself home projects.

We’ll teach you what these fasteners are, the different types of screws that can be used, and help you identify the best one for your job.

We’ll also provide tips for using lag screws correctly and safely to best secure your project.

With the right supplies and our help, you’ll be able to choose lag screws confidently, confident that you are making the right purchase and that you will achieve the desired results.

What Sets Lag Screws Apart


Lag screws are incredibly useful fasteners that provide an easy, secure way to attach more than one material together.

Lag screws have several advantages for the everyday user, such as being strong and durable.

They’re made from corrosion-resistant metals such as stainless steel and bronze, so they won’t corrode when exposed to humid and wet environments.

Lag screws also offer a high clamping force, allowing them to provide a very secure connection.

Additionally, they’re easy to install and can be quickly tightened and loosened for a custom fit every time.

For projects that require extra strength, lag screws are a great choice.

Lag screws also don’t require additional nuts and washers − making them the perfect choice for those who want a simple and strong connection between two materials.

How Lag Screws Work

Lag screws, or lag bolts, are a special type of screw used to secure wood or other materials together.

They have a unique design that allows them to be twisted into wood and hold firmly in place.

The head of the lag screw will have a square or hexagonal shape, which allows a socket wrench to be used to tighten or loosen it.

The thread of the lag screw has a coarse pitch which creates a powerful hold.

Lag screws require more torque than other types of screws and have unique thread patterns that give them greater holding power.

This makes them ideal for woodworking projects where extra strength is necessary.

Features to Look For

When shopping for lag screws, it is important to consider the features that make them unique.

Start by checking the size and type of head the screw has.

Different lag screws have different configurations, so make sure the screw will work with your project.

Look at the threading too.

Coarse threading will have larger gaps between thread spirals, and work best for softer materials, while fine threading has a closer gap between spirals and works better for harder materials.

Lastly, consider the grade of the lag screws - higher grade screws are made of higher-quality materials and will last longer than lower-grade screws.

When you find the right combination of features, you can be sure your lag screws will do the job you need for it.

When to Use Lag Screws

Common Applications

Lag screws have become a popular choice for many applications.

They are commonly used in construction and DIY projects.

Common uses include fastening wooden beams, posts, and outdoor decks to concrete foundations.

Lag screws are often used in fencing applications, too.

They provide a strong and secure way to attach lumber and other materials to posts or to a wall.

Additionally, lag screws can also be helpful for securing large furniture to the wall, or for joining two boards together.

With such a wide range of uses, it’s no wonder why lag screws are such a popular choice among DIYers and professionals alike.

Lag Screws In Your Workshop

Lag screws can be a great addition to any home workshop.

They are ideal for use in woodworking projects, as well as other DIY tasks.

Lag screws are strong enough to be used in place of other tools, such as nails, hammers, and even pulleys.

Plus, they are easy to maneuver and can be quickly installed with just a drill and a screwdriver.

Lag screws are also more durable than regular screws, and can even be used in combination with traditional tools to help secure a project in place.

So, if you’re looking for a powerful and versatile addition to your workshop, lag screws are the way to go.

Techniques and Tips

When using lag screws, it’s important to follow a few key techniques and tips.

First, be sure to pre-drill a pilot hole that’s the same size as the shank of the screw or slightly smaller.

This helps prevent the wood from splitting.

After that, add a bit of lubricant, such as a graphite mixture, to the screw threads before screwing it in.

This makes it easier to drive the screw into the wood.

Make sure that you tighten the lag screw securely, but don’t overtighten it.

Use a socket, wrench, or screwdriver for the job.

If the screw is too long, make sure you cut off the excess with wire cutters.

Lastly, be sure to use corrosion resistant screws so they last longer and don’t rust.

What To Look For In Lag Screws

Lag Screw Options

When buying a lag screw, you have plenty of choices.

You can buy screws that are short and slender, or screws that are long and thick.

You can choose a variety of finishes, like black, galvanized, or stainless steel.

You can also pick a varied range of diameters, from small to large.

You should also consider whether you want a pointy end or a flat end for the screw.

Whatever your project, there’s likely a lag screw that will fit the bill.

Consider the size, specifications, and finish before you make your selection.

Be sure to get the right size for your project.

Choosing the Right Lag Screw

When buying lag screws, there are some important options to consider.

The size of the screw is key, so make sure to get the right size for the project.

For outdoor projects, look for the stainless steel or zinc-coated steel screws that will hold up better in damp conditions.

It’s also important to note left-handed or right-handed screws.

Left-handed threads twist counterclockwise, while right-handed threads twist clockwise.

Additionally, shorter screws are better for soft materials like wood, while longer screws can handle tougher materials.

Finally, pick the specific type of head design that will best fit your needs.

There are flat, oval, and hex heads for lag screws.

Taking the time to review all the options will ensure you select the best lag screw for the job.

Brand Reliability

Hilman manufactures reliable lag screws with superior corrosion protection and high tensile strength.

Simpson Strong-Tie is also a great choice for lag screws with their patented sidestrand technology that increases the screw’s shear value for greater durability.

Grk Fasteners are designed for long-term performance in demanding conditions and are available in a range of sizes to suit various building projects.

Finally, SplitStop’s lag screws are designed to help protect wood from splitting, ideal for outdoor projects with multiple weather changes.

These brands have a solid reputation for delivering quality lag screws for a wide variety of jobs.

Safety Measures and Precautions


Lag screws can cause a variety of problems if they are not installed correctly.

If the screw isn’t long enough, it won’t secure the piece into the wall properly.

This can lead to a loose and unstable construction which could be dangerous.

To fix this, buy a longer lag screw and make sure it is the correct size for the job.

Additionally, if you don’t drill a pilot hole, the lag screw won’t be able to hold properly.

Make sure the pilot hole is the proper size for the screw you are using.

If you’ve made a mistake, try to extract the lag screw and use another one.

If the material is too hard, ask a professional for assistance.

If you follow the steps and use the right tools, you can avoid troubleshooting lag screws.

Maintenance and Upkeep

It’s important to check your lag screws regularly to ensure they’re safe and secure.

Always inspect for any broken parts or rust, and repair or replace any damaged screws.

Make sure to use proper lubricants to help keep the screws working properly.

Keep in mind that if your lag screws are consistently exposed to weathering, corrosion can occur, so you should take the necessary measures to protect them.

Additionally, the screws should be cleaned periodically using an appropriate solvent, and you might benefit from using a sealant to further protect them.

Remember to stay mindful about proper maintenance to keep your screws in good condition.

Staying Safe

When purchasing a lag screw, make sure you wear protective eye-wear.

When using a lag screw, never use your bare hands, always have a sturdy pair of gloves.

If possible, utilize a safety harness when climbing ladders.

Additionally, make sure the tool you are using is in good working order and properly grounded.

If you must use a ladder, don’t leave it leaning against the job surface.

Always stay away from wet locations and never handle the lag screw if it is hot from welding.

Regularly inspect your equipment and cords to make sure there are no frayed areas.

Finally, make sure you store all tools away safely to prevent accidents.


Buying Lag Screws

Buying lag screws doesn’t have to be difficult.

Start by understanding what size you need, and how many lag screws you’ll need for your project.

Shop around and compare prices to make sure you get a good deal.

Check to make sure the screws you’re buying are made from high quality materials.

Read reviews and get feedback from other buyers to make sure you’re getting a quality product.

Finally, know that lag screws can be used to secure a variety of materials, so make sure you’re buying the right one for your job.

With a bit of research, you’ll be able to find the lag screws that best fit your needs.

Home Power Tools

Your All-In-One Guide to Home Power Tools