Convert measured roof surface area to roofing squares, add one clear waste allowance, and optionally estimate whole shingle bundles or material cost. One roofing square is exactly 100 square feet.
A roofing square is an area unit used in US roofing estimates. One roofing square equals exactly 100 square feet; it is not the same as one square foot.
Use actual sloped roof surface area here. If you only know the building footprint, calculate the sloped roof area first with the Roof Area Calculator.
roofing squares = roof area in ft² ÷ 100area in ft² = roofing squares × 100planning area = base area × (1 + waste % ÷ 100)exact bundles = planning squares × bundles per squareexact bundles = planning area ÷ coverage per bundlesquares covered = bundle count ÷ bundles per squareA 2,350 ft² roof equals 23.5 roofing squares. With 10% extra, planning area is 2,585 ft² or 25.85 squares.
At the editable example rate of 3 bundles per square, 25.85 squares needs 77.55 exact bundles, so buy 78 whole bundles.
18.5 roofing squares equals 1,850 ft², or about 171.87 m².
For 2,585 ft² with manufacturer coverage of 33.3 ft² per bundle, divide planning area by 33.3 and round the purchase count upward.
Pitch is not calculated here. Use Roof Area Calculator when starting from a horizontal footprint.
Three bundles per square is a common example only. Bundle coverage varies by shingle product, so use manufacturer coverage when available.
Optional ordering increments always round upward and never change the exact result.
The estimate excludes labor, tear-off, underlayment, flashing, ridge caps, fasteners, delivery, and taxes.
A square foot is a standard area unit. A roofing square equals 100 ft², so 1,500 ft² is 15 roofing squares. Likewise, 10, 20, and 30 squares equal 1,000, 2,000, and 3,000 ft².
Metric input is converted through the shared area converter to square feet before division by 100.
Waste is applied once to base roof area. Planning squares and bundles both derive from that adjusted area, preventing a second hidden waste multiplier.
Bundles per square is useful when a product specifies that ratio. Coverage per bundle should be preferred when the manufacturer publishes usable coverage.
No rounding is the default. Optional ordering squares are ceiling-rounded while exact planning squares remain visible.
This tool does not calculate pitch, ridge caps, starter shingles, underlayment, flashing, nails, labor, structural requirements, or code compliance.
It is an area unit equal to exactly 100 square feet.
There are 100 square feet in one roofing square.
Divide roof area in square feet by 100.
It is 20 roofing squares before waste.
It is 25 roofing squares before waste.
Multiply roofing squares by 100.
Convert square meters to square feet, then divide by 100.
Add an appropriate allowance to measured roof area once, then derive planning squares from it.
No. Product design and package coverage vary; verify manufacturer specifications.
Keep the exact decimal for estimating and use upward rounding only when purchasing requires it.
No. Use Roof Pitch Calculator or Roof Area Calculator first.