Some DIY projects are for fun, like building a new piece of furniture or a tool shed to store your favorite items. A roofing project is serious! This is something you need to get absolutely right, as the structural integrity of your home as well as the safety of your family is at stake. You need to get the entire process perfectly correct, right down to buying the right type of roofing nails.

This includes finding the right materials, usually either hot dipped galvanized nails, stainless steel nails, or even copper roofing nails if the roofing materials recommend it. This also means choosing the correct length. Yes, the length matters! So, the question becomes- How long should roofing nails be?

First, we should point out that roofing nails should be made of galvanized steel, stainless steel or copper. They should have a nominal shank diameter of 11 or 10 gauge and a minimum head diameter of 3/8 of an inch. A roofing nail has a diamond-shaped sharp point to help it nail through decking without splitting it. That is why it is important to use only roofing nails when doing a roofing job. Nails should have smooth shanks, although ring-shank nails and nails with shank deformations such as “barbs” may be used if that's what you prefer. If you don't start out with the right type of nail for a roofing job, it won't matter what length they are because they'll degrade and rust quickly enough for the project to need to be redone anyway!

Now, let's discuss the length. Nails should be long enough to penetrate 3/4 of an inch into a roof deck. If your roof is less than 3/4 of an inch, your chosen nails should be long enough to penetrate and extend at least 1/8 of an inch through the roof deck. When determining nail length, be sure to consider the number of layers of shingles, shingle thickness, underlayment, as well as flashings. Always consult the shingle manufacturer’s recommendation.

You may be wondering "Wait- won't I be able to see the nails?" Actually, yes! It is important to note that when the bottom side of a roof deck is exposed to view, using nails of the recommended length can often result in the nail points penetrating through and being seen. In this case a shorter nail can be used but only on the eaves or edges of the roof for cosmetic reasons. In the main field of the roof, where the attic space is, longer nails should be used for maximum embedment. 

Planning and executing a good roofing job requires knowledge of every aspect of the job. Using the correct size of roofing nail will ensure that your roof stays intact for many years to come and can help you avoid the common problem of roofing nails that extract themselves over time and cause you to lose shingles. We hope this information answered any and all questions you had about finding the correct length of roofing nail. If it didn't, simply reach out and ask! Please feel free to give us a call toll free at 1-877-593-2723 or email sales@fastenerusa.com.