Choosing the right fastener for your home improvement project can be daunting. Should you use a screw or nail? How long does it need to be? Galvanized? Hardened? Brass? So many options means lots of ways to make a mistake.
I’ll walk you through the most important points and help you make the right choice when it comes to your next project. There are countless specialty fasteners that will defy the details I’m going to talk about here. This post is about general carpentry uses and a few of the more useful specialty fasteners. Today, we’ll talk about nails and next week we will dive into finding the right screw for the job.
What Length Nail Do I Need?
This has got to be the most common question when it comes nail selection. Every building code requires different things so you are best to check your local rules and regulations. That being said, there are two prevailing rules of thumb to help you determine proper nail length.
- Rule of Thumb #1 – Use a nail that is at least 3 times the length of the material you are nailing through. For example, if you are nailing 1/2″ sheathing on an exterior wall you should use a nail that is at least 1 1/2″ long. 1/2″ x 3 = 1 1/2″.
- Rule of Thumb #2 – Use a nail that will penetrate the item you are nailing to (not through) at least 3/4″. So, to use the same example of 1/2″ sheathing you would need a nail that is 1 1/4″ long. 3/4″ + 1/2″ = 1 1/4″.
Whatever length you use, you can’t really overbuild. If you are going to err on nail length, always err on the side of using too long of a fastener rather than too short. Just remember, you don’t want your nails being too long that they blow out the back side of your work.
Understanding Sizing
Nails are sold according to penny size. 8d, 12d, 16d where ‘d’ stands for the penny from the British monetary denomination. This sizing has been around for a loooong time and originated from the price of 100 nails centuries ago. For example, 100 8d nails used to cost 8 pennies and 100 16d nails cost 16 pennies. Penny sizing refers to the length of the nail. The larger the penny number, the larger the nail.
There is another type of sizing that relates mainly to nails for pneumatic nail guns (specifically finish nailers). Fasteners for nail guns are sized according to gauge (ga.). From largest to smallest, you have 15-ga., 16-ga., 18-ga., 21-ga. and 23-ga. Unlike penny sizing, gauge refers to the thickness of the nail and not the length. You can have various lengths in each different size gauge. For example, you can buy 15-ga. nails in lengths from 1″ to 2 1/2″.
- 15 & 16-ga. Nailers – Called finish nailers, are the largest nails and typically used for applications like door/window jambs, baseboards, large crown molding and fastening other significant pieces of wood that are not structural.
- 18-ga. Nailers – Called brad nailers, shoot smaller nails than their 15 & 16-ga. cousins. They don’t have quite as much holding power but they are better for smaller trim because they don’t leave as big of a nail hole and also lower the risk of splitting delicate trim pieces.
- 21 & 23-ga. Nailers – Called pin nailers. These nails are usually so small they have no head and therefore minimal holding power. These are best used for holding very small pieces of trim with the assistance of glue. Of all the nailers in my arsenal I use these least.
If you’re looking for a good all around nailer, then I’d suggest the 18-ga. for its versatility.
There are other nail guns that are for specific uses like framing nailers, roofing nailers and siding nailers. These nailers work much the same way as finish nailers but they shoot larger nails that are appropriate for the different applications they represent.
Interior or Exterior
If your project is going to be exposed to the elements, then your fasteners need to be up to the task. You can’t use interior nails on the outside and expect them to last very long. Interior nails will rust and bleed through the paint and eventually fail. So, there are four types of exterior nails that you’ll need to know.
- Electro-Galvanized – These are steel nails that are given a thin coating of zinc to add rust resistance. This coating is kind of the bare bones of rust prevention. In my opinion, electro-galvanized nails give you a few more months or possibly an extra year before the rust sets in. They are an option, but not one that I recommend.
- Hot-Dipped-Galvanized – These are steel nails again that are dipped in molten zinc during the manufacturing process. This creates a much thicker coat of zinc that has plenty of staying power to prevent rust for many, many years. These are also the recommended fasteners for pressure treated wood and cedar which can cause standard nails to corrode quickly.
- Stainless Steel 304 – If you want the premium product that is guaranteed not to rust, that would have to be stainless steel. Be aware that you’ll pay a big premium for stainless nails. The number 304 refers to the blend of alloys in the steel that make it have those amazing stainless properties. For most exterior applications 304 is the most appropriate grade of stainless you’ll need.
- Stainless Steel 316 – This is the mac-daddy of exterior fasteners. 316 steel has chromium, extra nickel and added molybendum (whatever that is) mixed in with the steel to make sure it can stand up to the most brutal conditions. If your project is being built on the coast where it will be subject to salt water spray or other conditions that are particularly rust inducing, 316 stainless is what you need.
Shank Patterns
There is a nail for every task. And a different shank pattern for many tasks as well. Here are a few of the most common and what you would use them for.
- Common – This type of nail your standard all-around nail. It has a smooth shank and no frills. From framing walls, to attaching trim (pneumatic nails are almost all smooth shanks) this is your baseline nail.
- Coated (Sinker) – I use these nails most often for framing when I’m not using a framing gun. They have a thinner diameter than common nails and a thin coating on them that when subjected to the friction of driving a nail allows them to sink into the wood more easily, hence the name “sinkers.” That same coating when it cools functions a bit like a glue to hold the nail in place.
- Ring – Ring shanked nails are my favorite for installing wood siding and roof decking. Anything that needs extra holding power to protect against strong winds and uplift is a good candidate for ring-shanked nails. The ringed shank adds significant holding power to help keep the nail in place.
- Spiral – These are excellent nails for use with hardwoods. They spin as they are driven which gives them additional holding power over a common nail and its spiral shank helps prevent splitting wood.
There is really so much more to talk about when it comes to nails, but I don’t have time for an encyclopedia-like post here. This should be a good primer to cover the most important things you need to know when it comes to finding the right kind of nail for the right job. If you have any doubts about which nail to use, you should always check with your local building codes since their requirements can vary across the country.
Feel free to comment here with any questions you might have about which nail is best for your project and I’ll answer in the comments below.
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I love old houses, working with my hands, and teaching others the excitment of doing it yourself! Everything is teachable if you only give it the chance.
Exterior project. Building a privacy wall for our hot tub. 8ft tall X 12ft in length. Used 4×6 treated posts on the end, with (2) 4×4 posts in the middle. Going to nail 1x6x12 tongue and groove cedar boards the full height of the wall. I have a framing nail gun and a finishing nail gun. Which gun do you recommend and what type/size nail? Don’t want to split the boards. Also I operate them off a small air compressor. Do I need to adjust the air pressure? Thanks for any insight you can give me.
Thank you for this. I am trying to put pvc trim around sliding glass door on outside of house. We are going into stucco. We tried 18ga with our nail gun before reading this. Should we try 16ga or is there a better way to place trim over stucco? Thank you!
Thank you for sharing may favorite tips. I allso agree with But most of the times, when I go to the store, the product isn’t available. So I bought the tool that I want without any consideration. So I really appreciate that you post this great information.
I am okay a planning, but poor in execution. I am making a small organizer for mobile devices and a USB charging station. All the wood will be 1/4″. What is the recommended fastener for this and can a pneumatic finishing nailer be used for this? Thanks in advance for your help!
What size nail and nail gun do you think would work best for fastening the pickets on a fence? I was thinking 2″ ring shank SS nails. Would that typically be used in a framing nailer or a 15 ga. or a different size?
A local fence company in TN uses 16ga 2″ hot dipped ring shanked nails. Hope this helps.
Hi Scott
I have a 21 degree framing nail gun and want to attach exterior grade 2 x 4’s to 1 x 4’s on an existing swing set. Which size and type of nail should I use? I’m thinking either 2-1/4 or 2-3/8” smooth shank but not sure if the longer nails will protrude through the 1 x 4. Thanks for you help.
Can you go into greater detail about structural nailing like you did with finishing?
I think the issue I experienced was more related to the soft pvc material the trim was made from than the nailer. I switched to 18 and finished the project with no additional problems. Some of the area around the larger nails did heal a little over the next few months but never looked as good as the 18’s
I have a 18 ga Craftsman brad nailer that I want to use to install 1×6 pressure treated skirting under my deck. Would you suggest 1.5” 304 SS brads for this application?
I’d probably use a 16 or 15 ga nailer and 2 or 2 1/2” nails if it were me.
Cool! That’s a clever way of looknig at it!
I like how you say that you would want to consider a fastener that is three times longer than the material you are working with. it would seem that you would want to do this to be sure that it is tightly fastened. My brother is looking for a fastener, so he’ll have to choose some that are long enough.
The guys hanging my 1″ Hardie pre-painted trim used a nail that has a 1/4″ (or slightly larger) head that is either just flush or in many cases, sticks out a little. I’m not convinced they’re the right choice, but how do I fix them, since I wasn’t planning to paint?!
I’m putting up ship lap on the walls that is 1X10 what type of nail would you recommend. We are going with more of a rustic look at the cabin.
Our contractor used a silicone caulk to seal the split lines between Hardie Panels during installation. Now it is time to paint our house and the contractor is recommending covering the split lines with primed and 3/4 in pine screen moulding (3/16 thick), then painting the house. What nails should I use? I think they need to be long enough to sink into the house framing, which is covered by Hardie Panels (5/16 thick).
I purchased a Hitachi 15 gu. nailer and used it for edge boards on a hardwood floor that I face nailed where I could not reach with the floor nailer. The size of the rectangular hole made by the nailer is significantly larger than the nail heads (approx. 5 times as wide as the head). Is this normal for 15 gu.?
I am thinking about investing in an 18 gu. brad nailer for the base boards to reduce the hole size.
Trent, that doesn’t seem Neal to me thought each gun is different. There shouldn’t be any hole other than the size of the nail if it is a quality gun and its tuned up. Hitachi is a good brand though so that surprises me.
Sounds like a combination brad/staple gun. Dedicated brad nailers will not have a hole larger than the nail head.
15 gauge nails have a significant larger head and mostly good for exterior work in my opinion.
18 gauge is the best all around for most projects but, with hardwoods I would normally use a 16 gauge then putty the holes. Hope that helps.
What size nail (gauge) should i use for the installation of 3/4 by 6 tung and groove ceder wood on the under side of my porch roof. (Porch ceiling)
I’d use either 16 or 15 ga. Anything smaller might give you problems since it’s on a ceiling.
Thank you for sharing your experience and tips. I usually browse the internet first to find out which tools that has the best price and quality. But most of the times, when I go to the store, the product isn’t available. So I bought the tool that I want without any consideration. So I really appreciate that you post this great information.
I am rebuilding my newel posts on my 1870’s Victorian that I have restored. I tried 18G 340 SS 2 inch brads to attach a 1.25 inch deep by 1 inch tall band molding (cedar, painted) to the bottom of the post to extend the bottom stair tread line around the post. Using Porter Cable gun on pancake compressor. The brads go in the trim but “curve out” the side without penetrating the 1.25 inch thick trim into the PVC post box behind. I bought 16 G 340 SS nails for my other gun to see if that works better. Am I doing something wrong? My 23 G pinner has done this with SS pins as well.
John, sometimes the grain in old wood can brad nails to curve out and not go where you intend. It happened to me this week as well in some pressure treated wood. Try nailing at a different angle and see if that helps.
I’m working on installing a deck. I have a 21 degree framing nailer that I’d like to use. Normally, I would always use screws to attach decking, but I’d like to consider nails because:
1) We’re using 2×6 decking (long story) instead of 5/4 so board popping seems less risky
2) Large deck, so efficiency would be appreciated
Any thoughts on how to do this? Do they make a galvanized spiral shank that can be delivered through a pneumatic nailer? I cannot seem to find them, which probably answers my question.
thanks,
Mike
Mike, spiral shank I don’t know, but I use a galvanized ring shank nail in a coil siding nailer. I think Hitachi makes the nails for it and it works great. Don’t see any problem using the nails except that it will be a royal pain to remove damaged boards or replace the decking when the time comes.
This was really helpful. We recently have needed to do some roofing repairs. I am going to look into the ring shanked nails for the protection against the strong winds. I would love to see how it holds up.
Great article – I think these days if you find the right source you can get Stainless Steel Nails to be not so expensive – and they look great!
A very informative primer on a subject that can be quite confusing. It is shocking to see how some people will use whatever is handy to put things together.
You really nailed it (sorry).
Ha ha! Thanks Art!