How many bundles of roofing shingles to cover 1200 square feet?

Four bundles of design(architecture) to 100sq = 48 bundles

Three bundles of three tab to 100sq = 36 bundles

The surface area of a roof is measured in "squares" of shingles. Each square covers 100 square feet. However, when you buy shingles, they're usually priced per bundle.

Calculate the number of bundles needed by measuring the roof's square footage (length X width). Divide that number by 100 to get the number of squares needed. Multiply the number of squares by 3 (in most cases) or the number of bundles it takes to equal one square. Again, in most cases 3 bundles = 1 square.