A Roofing Square is 100 square feet (100.0 ft2). A square is a common measure of area used in roofing. A common bundle of shingles is one third of a square.
Use the Metal for a Roof calculator to compute the metal panels for a roof. The formula works for gabled roofs with one or two sides(see diagram). For two sided gabled roofs, this formula is only accurate if the both gables have the same pitch, which puts the ridge in the middle. If the sides have different dimensions, calculate each side separately.
The Roofing Shingles Cost Survey list the observed price of a bundle of shingles. A bundle is equal to roughly (33 1/3 ft2) or one third of a square (100 ft2). The survey includes a date, the name of the store, and the five price points for shingles: economy, low, median, high and premium.
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:
All prices are for one bundle of shingles which cover 33.33 ft2.