Roof Pitch & Roofing Takeoff Calculator
Convert pitch and estimate sloped roof area, squares, shingles, underlayment, simple-roof metal panels and roof-edge quantities. Enter the geometry and product coverage for your roofing scope.
Roof Pitch & Roofing Takeoff Calculator
Calculate pitch, sloped roof area, squares, shingles, underlayment, metal panels and roof-edge quantities.
Need a Complete Roofing Takeoff?
Get drawing-based roofing quantities, accessories, flashing and related scope from your plans and specifications.
Roofing Takeoff ServicesHow to Use the Roof Pitch Calculator
- Choose roof type and enter dimensions or measured projected area.
- Enter pitch as rise, degrees or percent slope.
- Select roofing material, coverage and waste; review edge and valley inputs.
- Calculate and review quantities. Recalculate after changes.
Choose the Roof Type
- Simple Gable: two equal-pitch planes meeting at a ridge. The tool calculates ridge length, two eaves and four sloped rake edges.
- Shed / Single Slope: one plane spanning the full roof width. The calculated eave is the low eave; the upper horizontal edge is not included in drip edge.
- Simple Hip: a rectangular, equal-pitch roof. Ridge length follows the difference between the longer and shorter roof dimensions; square plans have no ridge. Hips use direct three-dimensional geometry.
- Complex / Area Only: enter an already measured projected roof area. This mode applies one pitch multiplier to that area; it does not reconstruct intersecting planes or infer their edges. For different pitches, calculate the measured areas separately.
Enter Dimensions and Overhangs
For a gable, building length runs along the ridge and width spans between the eave sides. Side/eave overhang extends both sides of the width; gable-end overhang extends both ends of the length. These horizontal extensions are added before pitch is applied. In Shed and Hip modes, the single overhang value extends both horizontal dimensions.
Use Identical sections only for matching roof sections. Areas and calculated linear quantities multiply by this count. Enter manual valley length per section when using identical sections.
Enter Rise, Degrees or Percentage Slope
A 6:12 pitch rises 6 inches for every 12 inches of horizontal run. That is a 50% slope, approximately 26.565 degrees and a 1.1180 pitch multiplier. Choose Rise : 12, Degrees or Percent to enter the same slope in another form; percentage slope is not the angle in degrees.
Projected Area vs Actual Roof Area
The building footprint is the horizontal area enclosed by its length and width. The projected roof area also includes the horizontal overhangs. The actual roof area is the sloped surface that roofing must cover. Using footprint area alone can miss both overhangs and the extra surface created by pitch.
The roof pitch multiplier converts horizontal roof area to sloped surface area: actual area = projected area × multiplier. At 6:12, 2,000 SF of projected roof becomes approximately 2,236.07 SF of sloped surface. In Complex mode, enter projected area—not an area that already includes slope—or pitch would be counted twice.
Roofing Squares and Waste
One roofing square equals 100 square feet. Net squares are actual roof area divided by 100. Order squares include the selected roofing waste: actual area × (1 + waste percentage ÷ 100) ÷ 100.
The editable default is 10%. Select an allowance appropriate to the roof layout, material, cuts and project requirements; one percentage is not correct for every job. Roofing waste is applied once before shingle bundles and underlayment rolls are calculated. Edge materials have their own separate waste input.
Shingle Bundles and Ridge / Hip Caps
This shingle calculator uses your product's bundles per square. Three is the default, not a universal coverage rate. Order bundles equal waste-adjusted roofing squares × bundles per square, rounded up to whole bundles.
Enter the actual LF covered by each cap bundle. Gables use ridge LF; hip roofs use ridge + hip LF. The combined length is divided by coverage and rounded up. For example, the default hip roof has 10 LF of ridge plus 126 LF of hips: 136 ÷ 33 requires 5 cap bundles. Check coverage and installation details against the selected product.
Metal Roofing Panels
The metal roof calculator provides panel counts for Simple Gable and Shed geometry only. Panels run up the slope, eave to ridge on a gable and low eave to upper edge on a shed. Use net coverage width, rather than the overall sheet width including laps.
Panels per plane equal the roof dimension perpendicular to the panel run divided by net coverage width, rounded up. Gables have two planes; sheds have one. Panel length is the full slope length for that plane, and total panel LF is panel count × panel length across the identical sections. These geometric panel quantities do not receive the roofing-waste percentage; order squares remain a separate area allowance.
Hip and Complex modes intentionally omit exact panel counts because the entered geometry is insufficient for a panel layout. Confirm trims, laps, cutting allowances, available lengths and the final panel schedule with the supplier.
Underlayment, Drip Edge and Starter Strip
Underlayment Rolls
Enter the usable coverage per roll for the product and planned application. Rolls equal waste-adjusted roofing SF divided by coverage per roll, rounded up. This roofing material calculator does not assume every roll covers the same area.
Drip Edge and Stock Pieces
Calculated drip edge is eaves + rakes, increased by the selected edge-material waste. Divide that LF by the entered stock-piece length and round up for pieces. On a shed, the upper horizontal edge is excluded; measure any additional required trim separately.
Starter Edges
Select Eaves + Rakes, Eaves only or None to match the specified roofing system. The chosen edge length receives the same edge-waste allowance. The calculator does not prescribe one starter installation practice for every system.
Valleys and Complex Roofs
Valley LF is manually entered in V1. Measure it from the drawings or field conditions; the calculator does not infer valleys from arbitrary intersecting roofs. The entered valley length multiplies by identical sections. Complex mode leaves unsupported calculated edges at zero; those zeros do not mean the real roof has no edges or valleys.
Worked Roofing Takeoff Example
For a 50 × 40 ft gable, enter 1 ft of eave overhang, 1 ft of gable-end overhang, 6:12 pitch and 10% roofing waste. The roof projects to 52 × 42 ft. With the default product coverage and edge settings, the live calculator displays:
| Quantity | Result |
|---|---|
| Projected / plan area | 2,184 SF |
| Actual sloped roof area | 2,441.79 SF |
| Net / order roofing | 24.42 / 26.86 squares |
| Shingles at 3 bundles/square | 81 bundles |
| Underlayment at 1,000 SF/roll | 3 rolls |
| Ridge / eaves | 52 / 104 LF |
| Sloped rakes | 93.91 LF |
| Drip edge with 5% edge waste | 207.81 LF |
| Drip edge in 10-ft pieces | 21 pieces |
Switching that same gable to Metal Roofing with 36-inch net coverage gives 36 panels, a displayed 23.48-ft panel length and 845.23 total panel LF. Calculations use unrounded values; displayed numbers are rounded for readability.
Use This as an Estimating and Planning Aid
This roof takeoff calculator does not size rafters, design trusses or flashing, determine wind/snow loads, model intersecting roofs, infer valley geometry, estimate labor productivity or certify structural/code compliance. Verify measurements, product coverage, specifications and the complete project scope. All graphics are schematic and not to scale.
Frequently Asked Questions
How do I calculate roof pitch?
Divide vertical rise by horizontal run, then express it per 12 inches of run. A 6-inch rise over 12 inches of horizontal run is 6:12. Enter that rise or its equivalent angle or percentage in the calculator.
What does a 6:12 roof pitch mean?
It means 6 inches of rise for each 12 inches of horizontal run: 50% slope, approximately 26.565 degrees and a 1.1180 area multiplier.
How do I convert roof pitch to degrees?
The angle is the inverse tangent of rise divided by run. For 6:12, atan(6 ÷ 12) is approximately 26.565 degrees. The calculator displays the converted angle automatically.
How do I calculate roof area from footprint area?
First include horizontal overhangs to obtain projected roof area, then multiply by the pitch multiplier. If the measured area already includes slope, do not apply that factor again.
How many square feet are in a roofing square?
One square is 100 SF. Net squares describe the measured sloped surface; order squares add your selected roofing waste.
How many shingle bundles do I need?
Multiply order squares by the product's bundles per square and round up. Ridge/hip-cap bundles are separate and use linear coverage per bundle.
Can this calculator estimate metal roof panels?
Yes, for simple gable and shed roofs using full-slope panels and entered net coverage width. Hip and Complex modes do not produce exact panel layouts.
How do I calculate drip edge?
Add the calculated eaves and rakes, apply edge waste, then divide by stock-piece length and round up. Add any required edges outside the model separately, including a shed's upper horizontal edge.
Does the calculator handle hip roofs?
Yes, simple rectangular equal-pitch hip roofs. It calculates area, ridge and direct three-dimensional hip lengths. Shingle cap bundles use ridge plus hips.
Can it calculate valleys on a complex roof?
No automatic valley layout is generated. Enter measured valley LF manually. Complex mode uses your projected area and one pitch multiplier without rebuilding the roof planes.