How to Choose the Right Nails
How long a nail should you use for a 1-inch board or a 2-inch board? Eight-penny or 16-penny?
The accepted rule of thumb is the nail length should be 21/2 times the thickness of the wood you are nailing through. Thus, for 1-inch-thick material, you would use an 8-penny nail and for 2-inch-thick material, you’d use a 16-penny nail.
Nails sized by the “penny” system have a number and a small letter “d.” To gauge how long a nail is, divide the size by 4 and add a half-inch. Thus, for a 12-penny nail, divide 12 by four. You get 3, then add one-half; that’s 31/2 inches long.
If your work will be exposed to the elements or used in a very damp location, it’ll weather better if you use galvanized nails.