If a roof has 2,000 square feet of actual surface area, it contains 20 roofing squares before waste. Divide roof area by 100 to convert square feet to squares.
Why contractors use roofing squares
Squares provide a convenient unit for materials and labor. Shingles, underlayment and installation quantities are often discussed relative to the number of roofing squares.
Add waste after calculating the base squares
Hips, valleys, ridges and cuts create waste. Use the Roofing Square Calculator to apply a waste percentage and estimate bundles.
How many bundles are in a square?
Many shingle products use approximately three bundles per square, but packaging varies. Always check the exact product specification before purchasing.
Roof footprint is not always roof surface area
Slope increases surface area. If you are starting with horizontal footprint dimensions, use the Roof Pitch Calculator to understand the pitch multiplier, then build your budget with the Roof Replacement Cost Calculator.