The number of Roofing Nails for a Square of Shingles in HIGH WIND conditions is 522. This puts six nails on each shingle, where a square covers 100 ft2.
There are:
3 bundles/square x 29 shingles/bundle x 6 nails/shingle = 522 nails/square
Roofing Nails are used to attach shingles to sheathing on a roof. There are two densities used for the number of roofing nails needed per shingle, normal wind and high wind. This can be seen in the shingle diagram to the right. The top image shows four nails per shingle above the tab cuts. This is for normal wind conditions. The lower image shows six nails per single with a double nail above the two central tab cuts. This is for high wind conditions in exposed places like on the edge of bodies of water, on top of mountains or other exposed places with no wind breaks. High winds are experienced in areas with little cover from wind breaks. Such areas include deserts, prairies, mountain tops and areas adjacent to large bodies of water. High winds are also associated with areas prone to hurricanes.
Note that for both normal and high wind applications, the roofing nails go just below the sealant strip.
Roofing nails are sold by weight in many places. The weight of the nails is based on a 5lb box of 1-1/4" smooth shank nails having 978 nails. That's 0.0818 ounces per nail.
One should use the pricing for roofing materials that can be bought locally. However, the following prices are for different quality grades of shingles in the United States. The 3 Tab and Architectural Shingles Cost Survey lists the observed price of a bundle of shingles. A bundle of shingles is 33.33 ft2 for 3-tab shingles or 32.8 ft2 for architectural shingles. The survey includes a date, the name of the store. the five price points for shingles: economy, low, median, high and premium.
NOTE: Local pricing should ALWAYS, ALWAYS, ALWAYS be used! These price points are for estimation convenience only, and there is no guarantee on the prices of the product nor of their availability at the stated price.