Are hidden fasteners a good choice for deck boards?

[Tomhanks]

Hey everyone, what are the pros and cons of using hidden fasteners for deck boards on a pressure-treated frame? How well do they hold up over time compared to face screws, especially with seasonal changes? Thank you in advance!

[Downaski]

Hi Tomhanks, hidden fasteners give a cleaner look and make the deck surface smoother, which is great for walking barefoot. They work well if the boards are straight and dry. But with pressure-treated wood, which tends to move more with seasonal changes, hidden fasteners can sometimes loosen or allow the boards to shift. Face screws usually hold better over time, especially with wood that expands and contracts. They're also easier to remove if you ever need to replace a board. So it's really a trade-off between appearance and long-term durability.

[Tomhanks]

Hey Downaski, thanks for the explanation. Also, does cupping or warping tend to happen more often with hidden fasteners on pressure-treated decks?

[Downaski]

Yeah, cupping and warping can be more noticeable with hidden fasteners, especially on pressure-treated wood. Since the fasteners usually grip the sides of the boards instead of holding them down from the top, there's less force keeping them flat. If the wood starts to dry unevenly or twist with seasonal changes, hidden fasteners don’t always hold it in check as well as face screws do. That’s one of the trade-offs: nicer look, but sometimes a bit more movement.

[Tomhanks]

Got it, that makes sense. When you say hidden fasteners don’t always hold the boards in check as well, do you mean they’re more likely to pop out or just allow more movement overall?

[Downaski]

It’s more about allowing movement rather than the fasteners popping out. Hidden fasteners usually stay in place, but because they hold the boards from the sides, they don’t resist upward or twisting motion as strongly as face screws. So if the boards start to cup or warp, the fasteners might not stop that from happening as well as top-down screws would.

[Tomhanks]

Right, do composite boards have the same issues with movement, or do hidden fasteners work better with them?

[Downaski]

Composite boards tend to be more stable than pressure-treated wood when it comes to expansion, contraction, and moisture-related movement. Hidden fasteners usually work better with composites because the boards don’t cup or warp the same way wood can. Most composite decking systems are actually designed with hidden fasteners in mind, and they hold up well over time.

That said, composites still expand and contract slightly with temperature changes, especially along their length. As long as the fasteners are installed according to the manufacturer's spacing guidelines, they usually perform well and maintain a clean look without the same concerns you’d have with natural wood.

[Tomhanks]

Thanks for breaking that down. Sounds like composites are definitely easier to work with in that regard. Appreciate the help!