If you’re looking for a quick way to install a roof, you may be wondering how long should roofing nails be. The length of a nail depends on several factors, including the type of material being attached to the roof. Some materials require longer nails while others need little penetration. Sheds and garden houses, for example, don’t require the same level of penetration as a home with a large roof. Solid wood, on the other hand, needs a nail that is 19mm in diameter.
Roofing nails are generally 3/8-inch in diameter, but larger head sizes may expose the head in standard nailing locations. A recent IKO test found that ring shank nails were significantly stronger than smooth shank nails in wind and rain resistance. Those installing felt underlayment will want to use square-cap nails. These nails feature a square head and a smooth or coiled shank. A screw shank nail is also an option.
Another factor that affects the length of a roofing nail is the thickness of the decking. Most roofs are constructed with asphalt shingles, so most guidelines apply to this type of material. Roofing nails that are 1 inch or less thick are sufficient for attaching asphalt shingles, while longer nails are only required in a few rare applications. Additionally, longer nails are not commonly available in local roofing supply stores. However, if you’re working with a thicker roof, you’ll want nails that penetrate the decking completely or at least 3/4 inch.
Regardless of your chosen material, the length of nails is a very important factor when determining the final result of your roof. The correct length should penetrate the sheathing and protrude approximately 1/4 inch from the top layer. If the nails are too short, they may not penetrate the top layer of shingles, leading to an unattractive hump on the shingle surface. If you have a wooden roof, the length of the nails must be at least one and a half inches above this, as this is the minimum.
The proper length of roofing nails depends on the thickness of the roof deck. In general, the nails should penetrate one-eighth inch of the plywood. The nails should be three-fourths of an inch in diameter. Wood planks should be no thicker than three-fourths of an inch. If the roof has a wood panel deck, nails should be about 3/4 inch thick. If they do not penetrate that depth, the nails can cause buckling, corrosion, and raised tabs.
Copper roofing nails are commonly used for slate roofing and copper sheet metal work. Copper roofing nails require longer nails. Electroplated nails are thinner and electroplated, requiring no additional coatings. Electroplated nails are a good option for indoor use. Some roofers use copper nails because they’re more corrosion-resistant than aluminum nails. However, they’re not the best choice for residential roofs. A roofer’s choice of nails should depend on the type of roofing and the thickness of the shingles.