concrete screw guide
29/01/2021

Concrete Screws Guide

Many improvement and construction projects involve nailing or screwing into concrete. Common situations include:

  • Affixing sole plates to concrete floors.
  • Attaching metal conduit to a concrete surface.
  • Fastening steel post anchors to concrete patios.
  • Attaching shelf brackets to concrete walls.

If you’re like some DIYers and contractors, you find using concrete screws to be frustrating and difficult. However, when equipped with the right tools, fasteners and tips provided in this article, you can employ this useful fastener with ease and confidence. Learn more about how to put screws into concrete below.

How to Use Concrete Screws

Concrete screws provide one of the easiest ways to fasten fixtures to concrete, and unlike many other types of fasteners, you don’t need a shield or anchor for installation. You also don’t have to do any hammering. All it involves is drilling a hole, cleaning the hole and driving the screw in — which is why these fasteners are referred to as self-tapping concrete screws.

Concrete screw fasteners, known commonly as Tapcons, look similar to wood screws but have high-low threads, which bite the hole’s side tightly. They’re available in 3/16- and 1/4-inch diameters and in lengths as long as 3 3/4 inches. You can choose between Phillips- and hex-head styles and use them on various surfaces, including concrete block, poured concrete, brick and the mortar joints between the block and brick.

Key Considerations

Here are some important considerations to keep in mind when drilling your concrete screws:

  • Base materials: Harder base materials require less embedment to achieve satisfactory holding values. For Tapcon concrete screws, the allowable embedment ranges from 1 to 1 3/4 inches. The screw’s holding values depend on the base material’s quality.
  • Hole diameter: The diameter of the hole is critical when using Tapcons. The tolerance between the diameters of the Tapcon and the hole is extremely tight, and any variation will impact the holding values. Concrete screws of a certain diameter must be installed using a carbide drill bit with a specific diameter. If you want to use screws with a 3/16-inch diameter, you must drill a 5/32-inch hole, and if you want to use 1/4-inch screws, you’ll need to drill a 3/16-inch hole.
  • Hole depth: The depth of the hole in which a Tapcon will be inserted is also important. You must drill the hole 1/4-inch deeper than your concrete screw must fit. This additional space allows the dust created during tapping to fall out without affecting the installation. If you don’t create sufficient space when drilling, dust may fill the space and the screw may bottom out, preventing proper installation. This situation could also cause the screw to become stuck in the hole, preventing you from removing it or inserting it deeper.
  • Screw length: The screw’s length is also important. The necessary length will depend on how thick the fastened material is. A Tapcon’s embedment must be at least 1 inch but no greater than 1 3/4 inches. To figure out the required length of a screw for your application, add 1 inch to whatever the length of the material you want to fasten is. To determine the maximum length of a screw, add the material’s thickness plus 1 and 3/4 inches. Any screw within those numbers should work for your application.
  • Tapcon screw lengths: You should measure flathead Tapcons as an overall length since they’re countersunk, meaning the screw’s entire length will be countersunk into the fixture and embedded in the base material. For hex-headed Tapcons, measure from under the head, as it will stay outside the fixture you’re fastening.
  • Head styles: Tapcons come in two head styles — Phillips head and hex head, each of which is meant for different applications. The flathead with a 3/16-inch diameter requires a #2 Phillips screwdriver, and the flathead with a 1/4-inch diameter needs a #3 Phillips driver. Hex heads are hex washer slotted heads driven in with a nut driver. For the 3/16-inch concrete screw, the nut driver must be 1/4 inches, and for the 1/4-inch screw, the nut driver must be 5/16 inches.
  • Standard vs. stainless steel: The standard Tapcon, which is blue, is suited for indoor use where moisture isn’t present. These standard Tapcons feature a blue Climaseal® coating that protects against rust. The stainless steel Tapcon features a silver Climaseal coating, which provides additional protection against rust.

how to drill concrete screws

How to Drill Screws Into Concrete

Once you have the correct length and type of screw and get a hammer drill with a carbide-tipped masonry bit, follow the steps below for how to screw into concrete:

  1. Drill the hole: With your drill and bit, drill the hole through the material you want to fasten to the concrete surface. Make sure the hole’s depth is at least 1/2-inch deeper than the measurement the screw will need to fit.
  2. Clean out the hole: Using compressed air, a vacuum cleaner or wire brush, clean out any dust created when you were drilling.
  3. Insert the screw: After aligning the hole in your fixture with the one in the base material, insert the Tapcon through the hole.
  4. Rotate the screw: With a drill or wrench, rotate the Tapcon until its head is tight against the fixture’s surface. Ensure the Tapcon isn’t over-torqued, which might strip the threads in the base material, causing the screw to spin.

Our Concrete Screw Options

All Points Fasteners offers dependable, strong and durable concrete screws at an affordable price. A wide variety of service professionals — including HVAC, roofing and gutter contractors — come to us for our vast selection of concrete screws and other fastening options.

Our concrete screw selection includes both hex washer heads and Phillips flatheads and is available in quantities ranging from 500 to 8,000. All boxes include one masonry drill bit for drilling the right-sized hole.

Come to All Points Fasteners for All Your Concrete Screw Needs

At All Points Fasteners, you get more than just high-quality products at reasonable prices — you also get a customer service team devoted to helping you find the best fastener for your application. If you’re having trouble securing materials, we will track them down for you and provide you with as much information as you need before you begin your project. Just use the live chat feature on our website, call us at 800.483.6354 or fill out our online form.

We look forward to helping you find the perfect concrete screws for your project!