Helping to create a strong barrier, concrete board — also known as cement board — is commonly used to cover walls, ceilings and floors with complementary materials installed, often tile or poured cement. In order for the barrier to be strong, you need strong fasteners — that’s where the right screw solution can make a difference in your project.
So, what type of screws do you use for cement boards? We’ll go into all the details for you: what kind of screws for concrete board use, their pros and cons, and any best practices to keep in mind.
What Screws to Use With Cement Board
To best attach cement boards to your project fixtures, you should use screws designed specifically for concrete board installation. When you buy cement board, the manufacturer may provide these screws with your purchase.
If not, look for screws that are finished with a special coating that resists corrosion. Corrosion resistance is key because the cement in cement boards has alkali levels that will corrode regular nails.
Screws made specifically for cement boards will also feature small grooves directly under the screw head. This allows the screw to dig into the cement board for a sturdier hold. These screws have extra-sharp points paired with the deep, wide threads to help them sit flush against the board.
If you can’t access cement board screws, you do have a few other options. If you gravitate towards nails, utilize galvanized or hot-dipped nails only. These nails are often used in outdoor decking and roofing installations, so they have a similar corrosion-resistant coating that helps resist rust or fading from water exposure. In this specific case, they can also resist corrosion from the alkali state of cement boards.
Any other screw-type outside of galvanized nails and cement board screws will stop where the shaft widens and leave the head sticking up, which results in a weaker finish and interferes with the flooring, tile work or other materials used in your project.
Screws & Cement Boards: Best Practices
To smoothly install concrete boards, you should install a fastener approximately every 6 to 8 inches along the perimeter of the boards. When it comes to the size of the screw to use, it will vary based on the project and the fixture to which you’re trying to attach the cement board.
If you’re attaching a cement board to plywood (or similar underlayment), it will hold together with 1 ¼‑inch concrete board screws.
For thick or heavy metal fixtures, you’ll need 1 ⅝‑inch concrete board screws.
If you’re using galvanized nails, a general 1 ½‑inch galvanized nail should hold the concrete board firmly in place.
Make sure the screw head is slightly indented into the cement board. You ideally want it flush with the surface. Too deep will weaken the hold and too high can interfere with thin tile installations.
For flooring or wall installation projects, you may want to apply a thin layer of thin-set mortar (a blend of cement, very finely graded sand, and a water retention compound) under the cement board to prevent shifting or expansion. This is a trick many builders utilize for a stronghold. But, with this extra adhesive, you should still apply the nails or screws of your choice.
Even though cement boards can look and feel like drywall, remember that the interior of each material is completely different. We do not recommend using drywall screws in any cement board work. The fasteners used for drywall do not have corrosion and alkali resistance coating.
Therefore, if you want your cement board project to last a long time, skip the drywall fasteners. Cement board screws will tear up drywall, and drywall screws will deteriorate over time if used in cement boards.
How FastenMaster Can Help
FastenMaster’s PAMFast Cement Board screws are a great option for cement board, as they are designed for attaching USG Durock® and Hardiebacker® tile to wood on any site. The thread design and modified wafer head on the PAMFast Cement Board screws deliver a consistent countersink and holding power.
The screws come with the PAMDrive Recess, eliminating bit grinding and cam-outs. Whatever your project needs are (plywood, heavy metal fixtures, etc.), the PAMFast Cement Board screws come in 1 ¼” and 1 ⅝” sizes.
Paired with FrameFAST, you can change the way you frame with one screw, one tool and three interchangeable heads that give you accurate installation angle, precise offset and optimized thread engagement every time. With FrameFast, you can install five times faster than traditional connectors and drive job site productivity.
If you want to use galvanized screws instead, we recommend the FastenMaster ThruLOK Through-Bolt Replacement. The ThruLOK system combines the strength of a through-bolted connection with the speed of a LOK fastener with no predrilling required. On top of cement board, it can also be used for multi-ply beam applications, decks posts, carrying beams and more.
ThruLOKs replace traditionally carriage and through-bolts in applications ranging from 4 ½” to 9 ½”. It has a three-part assembly that includes a screw, a patent-pending Paddle Point™, an engineered washer and a LOK nut. It installs with an 18-volt cordless drill with no drill bits or wrenches required. And because of its galvanized coating, it meets the IRC ACQ corrosion requirement and makes itself suitable for cement boards for a lifetime performance guarantee.
Interested in learning more about FastenMaster and how we can help you with your cement board project? Check out our wide range of cement board products.
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