How many bundles of shingles are in a square?
Most three-tab and architectural asphalt shingles come about 3 bundles to a square (a square = 100 sq ft of roof). Heavier or specialty shingles can run 4 or more bundles per square, so confirm the coverage printed on the wrapper. Order 5–15% extra for waste, starter course, and hip and ridge caps.
Source: Roofing trade convention (check product wrapper) · Verify against your AHJ and the adopted code edition.
A square is 100 square feet of roof, and most three-tab and architectural asphalt shingles are packaged 3 bundles to a square. That’s why a bundle is a manageable ~1/3 of a square — light enough to carry up a ladder.
The number isn’t universal, though:
- Heavier and specialty shingles (thick laminates, slate-look, some designer lines) can run 4 or more bundles per square — the exact figure is printed on the wrapper.
- Starter strip and hip/ridge caps are usually separate products; don’t count them in your field-shingle bundles.
- Waste of 5–15% is typical for cuts and valleys — more on a complex, cut-up roof.
And remember a pitched roof’s area is larger than its footprint — you scale the footprint up by the slope before converting to squares.
Work it out: the roofing calculator takes a footprint and a pitch, applies the slope factor, and returns the roof area, squares, and an estimated bundle count with a waste allowance.