Brad and Nail Sizes Explained (2023)

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What are the different brad and nail sizes?

Here, you will have to check out the differences between brad nails and finishing nails.

Brad Nail Thickness

How thick are brad nails? Answer: 18 gauge. This is thinner compared to finishing nails. Since brad nails are so thin, they will keep a low profile in your projects. Where aesthetics matter, you can blend in the brad nail easily simply by using paint.

The thickness of finishing nails is a bit greater than brad nails. Finishing nails usually measure around 15 to 16 gauge. Since they are stouter, they can be better suited to tasks that require extra nail strength. As they are sturdier, they can be a better choice for holding heavier material in place like a bulky baseboard for instance.

Brad Nail Length

What is their length? They have a minimum length of 0.5 inches. Their length can extend up to a maximum of 2.5 inches.

Brad nails can travel as deep as ordinary nails. Using appropriate tools it’s also possible to have brad nails countersink below the wooden surface. Since brad nails are available in smaller sizes, they can work well for thinner materials that are less than one inch thick.

Brad Nail vs Finishing Nail

The thinness of brad nails can make them somewhat flimsy and thus tougher to work with. You might bend them easily if you are not careful while hammering them. Yes, it is possible to hammer them using the right technique. Of course, you will enjoy much greater consistency with a brad nailer.

But there are also limitations to finishing nails. Since they are longer and thicker, it may not be a good idea to use them on thinner wood materials. If you have to attach something delicate or flimsy, a brad nail may be a better choice. Some experts like to use brad nails towards trim ends since this is where they may likely split. Finishing nails may be too big for the sides of the trim.

Also, it is important that you use finishing nails if you are working with drywall. Brad nails don’t have the grip strength necessary for holding anything securely against the drywall. Brad nails are too flimsy for drywall which itself is rather soft.

So there will be excessive movement here. However, some folks still insist on using brad nails even in this case due to their low profile. For such cases, it may be advisable to use glue or adhesive for a high-strength grip.

How to Pick a Brad Nail Size that Works

A simple general rule can help you understand what brad nail size will work for your project.

All you have to do is to choose a brad nail size that is 3x thicker than the surface on which you are installing these nails. For example, if the trim material that you need to nail is 0.25 inches thick, then your brad nail should measure 0.75 inches long.

The trim material will have its whole thickness pierced by the nail. Plus, there will be plenty of brad nail length to pierce the supporting material underneath the trim. Hence, it is easy to see that such a length will ensure robust support for your trim.

Of course, it is imperative to realize that not all projects will require this much brad nail length. If you fear that the support material is so thin that the brad nail will stick out of the other side, then you can use a shorter brad nail length that will prevent this from happening.

But if there is no such consideration, you should think about using the 3x rule since a brad nail of this length will provide plenty of lengths as well as a grip for extra-resilient support.

Maximum Material Thickness on Which a Brad Nailer will Work

Brad nailers often drive just 18 gauge nails. Their maximum length is 2.5 inches.

Due to their relatively low length and the 3x rule mentioned above, this means that you don’t have much material thickness to work with. Remember that the brad nail length should be around 3 times the thickness of the material you are working on?

Keeping in mind the maximum brad nail length of 2.5 inches, this means that you cannot work on even an inch thick material. In fact, the material should be less than 5/6^th of an inch.

At this point, you might be wondering if it’s even possible to increase the brad nail length beyond 2.5 inches to remediate this limitation. Trouble is that brad nails can’t be longer than this length. This is due to their relatively thin 18 gauge. Thin nails can’t be too long otherwise they will bend, twist and warp easily when you fire them into the material.

Also, density and hardness matter of the material. Hence, if you are using a relatively low density and soft fiberboard, it won’t give your brad nails any trouble at all. Things change drastically when using hardwood though since it is so hard as the name suggests. It’s also dense too. Brad nails may not be able to penetrate 0.5 inches of hardwood without twisting and bending.

So how to know whether brad nails will properly penetrate the material without weird twists and bends? Just try it in advance on some scrap material to see how the brad nails look when you use them.

Check carefully to see that the brad nails are perfectly straight after you fire them into the material. If that is the case, then you are good to go.