All nails are made up of the same three major parts: the head, the shank, and the point. However, not all nail heads and shanks are the same. Some are shaped differently to serve specific purposes. General contractor Tom Silva explains how these vary to our host, Kevin O’Connor.
Nail Heads Explained
There are several different types of nail heads. They include flat, waffled, trim, and duplex.
Flat heads feature a smooth, flat nail head surface meant to pin material between the nail head and the structure below it.
Waffled heads are designed for framing hammers, as they provide a better bite on the nail to prevent slipping.
Trim heads are small, designed to be driven below the material surface with a nailset.
Duplex nails feature two heads. One for clamping material down to the structure and the other to remain proud of the material so it can be easily removed later, such as for framing and concrete form work.
Pro Tip: Tom Silva advises on picking the right nail length: “A nail should be two and a half times the thickness of the plank it goes through, but use common sense. If the point sticks out, shorten up.”
The Different Types of Nail Shanks
The nail shank is essentially the body of the nail, or the part of the nail that punches through one material and into another. Depending on the application, a specific type of shank might be a better fit:
Smooth shanks don’t have any ridges, rings, or other features. They’re ideal for quickly nailing materials together, though their holding power is minimal.
Ring shank nails feature barbed rings down the shank. These barbs bite down fiercely, making them a great choice for installing subflooring or when nailing to a sheet good rather than framing.
Pro Tip: Ring-shank nails provide maximum holding power and can actually speed up construction—where building codes permit, two ring-shank nails can replace three common nails. For framing, most carpenters rely on common nails, which have thick heads and thick shanks built to withstand blows from heavy framing hammers.
Spiral nails have twisted shanks that screw down into the framing material. They offer an extreme amount of holding pressure, making them a good fit for projects that need extra stability.
There are also important distinctions within the spiral shank category. Half spiral nails are easier to drive but still hold well enough to keep planks flat and squeak-free—making them a favorite of flooring contractors. Double spiral nails, on the other hand, are far more difficult to drive and remove, providing maximum holding power. Top-quality spiral nails are cut with a die rather than simply twisted.
Pro Tip: Tom Silva, This Old House general contractor, offers this advice on finish nails: “If you try to drive them flush, you’ll scar the wood. Drive them to head level, then sink them with a nailset.”
Different Projects Call for Different Nails
The nail to choose depends on the project at hand. If you’re framing, a smooth-shank nail with a waffle head might be a great choice. If you’re building concrete forms that you’ll need to remove later, a duplex nail is the way to go. Molding work? A trim nail is your best bet. Don’t want that subfloor to squeak in a few years? Go with a spiral nail.
