3 1/4 Or 3 1/2 Framing Nails? (We Have The Answer!)
When you’re framing the interior walls of a home, nail size is more important than you may assume. Nails that are too wide or long could end up slitting wood or be too difficult to drive. Whereas, nails that are thin or short may not effectively do the job.
If you’ve ever engaged in the construction phase of a home or building, you’ve likely wondered what exactly the difference is between 3 ¼ and 3 ½ inch nails, when it comes to framing. In short, the main difference has to do with nail length. In general, the 3 ¼ inch long nails work great in nail guns. Whereas, if you are hand nailing, 3 ½ inch framing nails are the better option.
Both can be used for framing, but which one you choose generally comes down to preference. Let’s dive in further in regard to their differences, characteristics, and how to choose the right framing nail for the job.
The Penny System
When purchasing nails in the United States, you’ll be using a sizing system that can be traced all the way back to 15th-century England. During this time, instead of identifying nails based on length, retailers used a “penny system,” and the old English abbreviation for penny is “d.”
A 16-penny nail, entitled 16d, will always be 3 ½ inches long, a 10d nail is 3 inches long, and an 8d nail is 2 ½ inches long. These specific lengths are among the most commonly used for framing.
3 ½ Inch Sinkers and Common Nails
Some experts suggest that nails that are 3 ½ inches long, or 16d, are the best sizing for framing. At your local hardware store, you will find two different types of 16d nails: commons and sinkers.
Common nails have a smooth, wider head than other types of nails at the same “penny weight.” Their heavy shanks allow them to support higher structural loads. 16d common nails have a diameter of 0.162 inches and are much heftier but may not be suitable for framing.
On the other hand, sinkers have a textured head that allows for a better grip of the hammer on the nail. 16d sinkers have a sleek 0.148-inch diameter and are constructed of a vinyl or epoxy that lets them to slide into wood effortlessly. This is especially useful when you have to drive a large number of nails in succession.
When framing interior walls, you want to use a nail size that isn’t too fat or too wide that you’d have difficulty driving it. Conversely, to be effective, it should not be too thin or short. This makes 3 ½ inch, 16d sinkers the ideal choice for use when hand driving for framing.
3 ¼ Inch Framing Nails
When you’re framing using a nail gun, it’s essential that you choose the right nail sizing for the job. Nails that fit into a nail gun will generally be fused together in rows for easy installment in the gun’s magazine.
If you’re purchasing framing nails from your local home improvement center, you want to ensure that they are recommended for your particular gun. However, when it comes to sizing, 3 ¼ inch framing nails, or 12d, are the preferred option for use in a nail gun by contractors and home DIYers alike.
The only physical difference between 16d and 12d as framing nails is the additional ¼ inch. Other than that, 16d is better for hand driving, and 12d works best in nail gun applications.
Other Nail Size Options for Framing
While 16d is the most recommended option for framing projects, there are other sizes that you can choose on depending on your preference. Let’s explore some other common nail sizes that could potentially be used for framing, including 10d, 8d, and 6d.
10d nails refer to the galvanized nails that are 3 inches long and 0.148 inches in diameter. This particular nail size works great in situations where you need to join two flat board faces. 10d nails are short enough that they won’t penetrate too deeply into the boards.
If you plan on using 10d nails, make sure that the application area is at least three times more than the diameter of the nail. This type of nail size is also ideal for framing roof trusses and are often used in framing studs.
8d nails are used for framing situations that require smaller sized nails. They are 2 ½ inches in length, their shank is 0.134 inches and the head diameter is 9/32 inches. Similar to 16d nails, 8d nails can be found as commons and vinyl-coated sinkers, depending on preference or individual situation.
This nail sizing is ideal for most siding materials. 8d nails are often used to attach sheathing, subfloors, furring strips, and any other materials that do not necessitate a larger nail size. However, when using 8d nails, always be sure to space them out so that they will pierce the stud.
Overall, 6d nails have the smallest diameter and are the shortest among all other framing nails. This makes 6d nails the perfect choice for use on small interior projects. These nails are 2 inches in length with a 0.12-inch shank and 17/64 inch head diameter.
Most often, 6dl nails are used to join flat woods and to nail finish floor or subfloor. Their smaller diameter and size make them less likely to cause any damage to the surface that they are nailed into.
General Tips for Using Nails
Consider the following tips when you’re using nails for framing, or any other purpose.
- If you’re working with harder woods or trying to drive into the end of a piece of wood, drill a pilot hole first to reduce the risk of wood splitting.
- Nails that are drive against the wood grain will lock into place. Whereas, nails inserted with the grain will slide out easier.
- Another way to avoid wood splitting is by blunting the point of your nail. Turn the nail upside down and tap on it a few times with a hammer. A blunt nail will be more difficult to drive but won’t split your wood surface.
- If you’re concerned about nail corrosion, use aluminum nails. Aluminum resists rust much better than rust-resistant nail finishes.
- Avoid placing multiple nails on the same line of grain. This will increase the stress on the wood and is more likely to cause it to split.
A better understanding of the various types of nails for framing, their sizing and uses can help you make an informed decision on the best nails for your project. Along with the above tips, your framing project should go off without a hitch.
Can you use screws for framing?
Both nails and screws can be used for framing. Nails are generally preferred for structural joining because they are more flexible under pressure, whereas screws are susceptible to snapping. However, for 2 x 4 framing, the coarse threads on screws can hold better than nails and are less likely to pop out of the surface when the wood contracts or expands. If you decide to use screws, you may have to use pilot holes to prevent splitting and it will generally take you longer to install them than nails.
Does framing have to be perfect?
Contrary to finish carpentry, framing does not have to look exactly perfect or please your desire to precisely fit two pieces of wood together. The main goals for framing are efficiency, accuracy, and strength.
Jessica considers herself a home improvement and design enthusiast. She grew up surrounded by constant home improvement projects and owes most of what she knows to helping her dad renovate her childhood home. Being a Los Angeles resident, Jessica spends a lot of her time looking for her next DIY project and sharing her love for home design.
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