How Long Should Roofing Nails Be?

Whether you’re securing shingles or installing a full-blown roof, you’ll want to choose the proper nails to ensure the long-term waterproofness of your roof. Roofing nails must penetrate all layers and achieve anchorage in the roof deck, which can vary. Depending on the material you’re using, nails can be anywhere from one to two inches long. This varies depending on the thickness of the roofing materials and the thickness of the sheathing.

The shingle type you choose will determine the length of your roofing nails. In general, you’ll need nails that are 1 to 2 inches long for asphalt shingles. Longer nails are needed for thicker, double-layer roofing projects. Wooden shingles, for example, require longer nails than fiberglass or asphalt shingles. However, these longer nails are difficult to find at your local roofing supply store. These longer nails are harder to work with and may have poor penetration.

The thickness of the decking on your roof will also affect the length of your nails. Most decking is less than an inch thick, so you may be able to use nails with a shorter length. Ideally, nails should penetrate at least 3/4 of an inch into the decking, and should even penetrate completely. For thicker decking, however, you’ll want to use longer nails. The thickness of your nails will also influence how well they attach to the roof.

Nails that defy gravity are often the cause of poor roofing installations. Their improper length forces the nails to back out of wood. This is dangerous because the nails must secure shingles, but they can back out when the nails are too short. It’s better to use nails that protrude at least a quarter inch through the roof deck before they’re able to penetrate. And if you’re wondering how long should roofing nails be, don’t worry – there are some tips that will help you decide on the correct nail length for your roofing project.

One-inch roofing nails are commonly used on roofs made of asphalt and fiberglass. While this is fine for most roofing applications, it’s not appropriate for securing wood shingles, which require longer and thicker nails. In addition, if you’re using asphalt shingles, you should avoid using nails that are smaller than the recommended size. You may also want to consider the extreme temperatures that can cause these materials to expand and contract.

When you’re installing asphalt shingles over an existing layer of dimensional shingles, make sure the nails penetrate the sheathing at least 3/4 inch. If you’re installing shingles over a 3/4-inch deck, use one-inch nails. But you can use one-inch nails if you’re replacing asphalt shingles on a plank deck. If you’re adding dimensional shingles, use nails with a head diameter of 9.5 millimeters.

Roofing nails come in three different materials. Aluminum, copper, and steel are the most common, but you can use stainless steel nails, too. But remember that a corrosion-resistant nail should penetrate the roof deck at least 3/4″ and extend about 1/8″ beyond the lower side. The length of the nails should be based on the number of layers of shingles, shingle thickness, underlayment, and flashing on your roof.