Foundational Fastener Matchup: Lag Screws vs. Structural Screws

Don’t stick with fasteners that lag. Have a faster, easier, and better build with structural screws.

It’s no secret that the foundation of the deck is what matters. The structural integrity of the load-bearing connections, like the ledger board, posts, handrails, and beams, are critical to giving you peace of mind that you’re building the best and safest deck possible for a family to enjoy for years to come. The typical go-to fasteners for these connections are lag screws (also known as lag bolts). While they still might be your dad’s choice for the deck structure, the industry has come a long way and now boasts highly tested and code-approved structural screws.

But how do the two compare? We’ll stack up CAMO® Structural Screws against lag screws, covering the design features, ease of use, and price and availability so you can make the best pick for your project.

Design Features

Lag screws are made to handle heavy loads and secure large pieces of wood together, and their design follows suit. Lag screws are beefy, with a significantly larger shank than a typical screw to help bear the load. They also have coarse threads that create a strong hold in the wood. Lag screws have an external hex head to secure boards together strongly.

Lag screws can either be zinc-coated, stainless steel, or hot-dip galvanized. The most popular option for temperate climates is hot-dip galvanization, which results in a thick coating that will wear over time but still offer excellent protection against corrosion for the lifetime of the exterior application.

Much sleeker in their design, structural screws are heat-treated to add strength instead of needing bulk or heft. CAMO Multi-Purpose Screws and Multi-Ply + Ledger Screws both feature a sharp point that starts fast, a Type 17 slash point that reduces splitting, an aggressive thread TPI and angle for increased holding power, and a straight knurl that reduces torque for easier driving.

CAMO Multi-Purpose Screws are available with a flat or hex head and each packaging includes a driver bit for jobsite convenience. The large flat head screws feature a T-40 star drive that reduces cam outs while the head maximizes pull-through holding power and finishes flush in your project.

Structural screws also come in more innovative coatings than lag screws. For instance, CAMO Structural Screws feature our industry-leading proprietary PROTECH® Ultra 4 coating system for superior corrosion resistance. Our hex head screws are also available in the standard hot-dip galvanized coating.

Ease of Use

All of the features of a lag screw that adds to their strength make them more challenging to install. Given their size, Family Handyman mentions you have to pre-drill two holes before driving the screw, one for the coarse threads, and a larger clearance hole for the shaft, taking a lot of time. Additionally, the external hex heads must be tightened with a wrench, which is time-consuming and can be exhausting..

Structural screws, on the other hand, are easier to use in any application. Structural screws don’t require pre-drilling; they thread their way through the wood while being driven. Plus, you can use a cordless drill for a fast install—just be sure to set the drill to the low speed and turn up the torque to the highest setting to let the screw do the work. Even with the CAMO Multi-Purpose Hex Head screw, the hex head with washer locks into a hex driver, allowing you to drive without holding onto the screw.

Family Handyman summed up the differences best, saying, “The labor difference is so huge that by the time you finish drilling pilot holes and ratcheting in just a few lags, you could have finished the whole job with structural screws and be sipping a cold one.” Need we say more?

Price and Availability

Price is the one area where lag screws edge out structural screws—but only on paper. They are about one-third of the cost of structural screws; however, the price you pay at checkout seems negligible when you think about the time savings you get with structural screws.

Regarding availability, lag screws have historically been easier to come by at home centers or lumber yards. But now, with various brands of structural screws available and multiple brick-and-mortar and online retailers offering different shipping and pick-up options, it’s easier than ever to get the fasteners you need.

When it comes to the structural connections of your deck, stop building like your dad used to. Get rid of lag screws and start using easy, fast, and code-approved fasteners for the job so you know your project has a rock-solid foundation.