We get this question a lot. Short answer: screws are good for holding deck boards down but galvanized nails work better for fencing.
Why nails are better for fences:
Nails are made from a softer steel than screws. This means they are more flexible and can handle lateral sheer without snapping. Screws are more brittle by design so they can hold their shape without stripping.
Nails also allow the wood to breathe a little more compared to screws. Less trauma means less splitting and cracking.
What does “galvanized” mean?
Galvanizing is a rust proofing process. The nails are dipped in hot zinc to create a silvery protective coating that keeps them from bleeding. Bleed occurs when moisture carries rust from the nail downwards leaving unattractive orange streaks running off the nail’s head. It’s the most visual characteristic of an ungalvanized nail. Galvanizing also protects the nail structurally from the corrosive effects of rust.
Why screws are good for decks:
The forces on deck boards are largely perpendicular (mostly down) with very little lateral sheer compared to fencing. The big concern is to keep the fastener from backing out of position and this is where screws really shine.
We enjoy fielding questions at the office. If you have any on nails or any other matter, call 613-736-1122 or hit the chat button on the right during business hours.