What Size Roofing Nails Do I Need?

Nails

• Most roofing nails have the familiar large head designed to hold fast to the shingle and keep the nail from slipping through. Aluminum or electro-galvanized steel nails are the most common nails and are used for asphalt shingles. Copper, stainless steel or durable, hot-dipped galvanized steel nails are required for slate, clay and concrete roofing because they are longer lasting.

Size

• Nail size depends on how thick the roofing material is and what kind of stress the nails will have to endure. One to 1 1/4-inch nails may be adequate for thin asphalt shingles, but 1 3/4- or 2-inch nails will be needed for slate and concrete tiles. Local building codes often dictate minimum nail length. Areas prone to tornadoes and hurricanes often have strict nailing requirements to make sure the shingles stay in place during storms.

Considerations

• Building codes often dictate not just nail length, but also the number of nails required. Consider, too, that flashing and roofing nails should be the same material. If you are using copper nails with aluminum or galvanized steel flashing, for instance, galvanic action -- an electro-chemical reaction -- will cause deterioration of both the nails and the flashing.

Finding a Contractor

• Look for a reputable contractor who is experienced in your roofing type. If you have a slate, clay or concrete roof, always find a roofer who is experienced in traditional roofing techniques. Ask your neighbors for recommendations and check with local authorities to make sure your contractor is licensed and doesn't have any legal actions against him.