Enter your Roof Length, Roof Width, and Roof Pitch, and the Roof Shingle Calculator works out your Total Roof Area, Roofing Squares, and exactly how many Bundles Needed — factoring in Coverage per Bundle and Waste Factor. Add a Price per Bundle to get your Total Material Cost.
Bundles Needed
--
Total Roof Area
--
Roofing Squares
--
Total Material Cost
--
A roofing square is a standard unit of measurement in the roofing industry that equals 100 square feet of roof area. It's commonly used to estimate materials and labor costs.
A standard bundle of asphalt shingles typically contains 20-29 individual shingles, depending on the size and type. Most bundles cover approximately 33.3 square feet of roof area.
Measure the length and width of each roof section at the base (footprint), then multiply by the pitch multiplier to account for the slope. For complex roofs, break it into simple rectangular sections and add them together.
The waste factor accounts for cuts around vents and edges, installation mistakes, damaged shingles, and future repairs. A 10-15% waste factor is typical for most roofing projects.
Steeper roof pitches increase the actual surface area compared to the footprint area. The pitch multiplier adjusts for this difference to ensure you order enough materials.
A bundle is the physical packaging unit (usually covers 33.3 sq ft), while a square is 100 sq ft of coverage. You typically need 3 bundles to make one roofing square.
Yes, always buy 10-15% extra shingles beyond your calculated needs. This accounts for waste, future repairs, and ensures you have matching shingles from the same production lot if repairs are needed later.
This calculator works for most standard asphalt shingles. For specialty shingles like slate, wood, or architectural shingles, check the manufacturer's coverage specifications as they may differ from the standard 33.3 sq ft per bundle.