How to properly nail shingles on a roof The preferred order for nailing is 1,3,2,4 but 1,2,3,4 is also acceptable. When the nails are placed in or above the self sealing strip that is called high nailing. High nailing can reduce the strength of the seal and make blow off more likely. Follow the application instructions on the shingle wrapper. If the deck is plywood the nail should penetrate through the deck. If the deck is solid wood the nails should be long enough to penetrate 3/4 of inch into the wood. Shingles at the hip and ridge may require longer nails for proper installation. Make sure that you use only zinc coated, steel or aluminum, 10-12 gauge barbed or smooth shank roofing nails, with heads 3/8-7/16's in diameter. Don't use common nails because they are not designed for roofing. Nails should be driven straight into the shingles and heads should be flush not driven into the shingle. Proper nailing keeps water from getting into the roofing system and premature failure of the roof. So be careful and go slow enough to do the job right and your roof will serve you well.