Framing, Drywall & Roofing
For roof pitch & shingle bundles at 8 × 10 ft gable roof at 6/12 pitch, the estimate includes 10% waste. The roof covers 0.89 squares. With the default allowance, order 3 bundles at three bundles per square.
Use the horizontal footprint of a symmetric gable roof, including overhangs.
ImperialCalcs · Contractor field tools
8 × 10 ft · 6/12 pitch · 10% allowance
| Item | Quantity | Unit rate | Amount |
|---|---|---|---|
| 3-tab shingles | 3 bundle | Unpriced | — |
| Ice-and-water shield | 1 roll | Unpriced | — |
| Drip edge | 38.361 ft | Unpriced | — |
| Roof footprint | Pitch | Squares | Bundles (3/square) | Drip edge |
|---|---|---|---|---|
| 8 × 10 ft | 6/12 | 0.89 | 3 | 38.36 ft |
| 10 × 10 ft | 6/12 | 1.12 | 4 | 42.36 ft |
| 12 × 16 ft | 6/12 | 2.15 | 8 | 59.78 ft |
| 16 × 20 ft | 6/12 | 3.58 | 12 | 76.72 ft |
| 20 × 20 ft | 6/12 | 4.47 | 15 | 84.72 ft |
| 24 × 24 ft | 6/12 | 6.44 | 22 | 101.67 ft |
For the 8 × 10 ft gable roof at 6/12 pitch, measure the eave parallel to the ridge and take the horizontal span perpendicular to it. Include the projection of both overhangs in these dimensions. If your drawing gives the wall dimensions instead, add the overhang on each side before using the worksheet. The entered span includes both roof planes, so entering the sloped width of one face would describe a different roof.
The pitch selector gives inches of rise per twelve inches of horizontal run. A six in twelve roof rises six inches over a twelve inch run. Half the horizontal span forms the base of a right triangle and the ridge rise forms its vertical leg. Multiplying the half span by the square root of one plus the squared rise-to-run ratio gives the length of one rake. Multiply by the eave length and then by two to cover the opposing planes.
The roof covers 0.89 squares. With the default allowance, order 3 bundles at three bundles per square.
Divide sloped square feet by one hundred to find measured squares. Keep the fractional square until the last purchase step. Apply the selected waste allowance to get order squares, multiply by the product’s bundles per square and round up once. Read the square footage covered by a bundle on the wrapper. If it covers thirty-two square feet, enter one hundred divided by thirty-two as the bundle rate. Using the actual coverage matters most when a small difference pushes an order over a whole bundle boundary.
The two bundle counts are alternative orders for the same field area. Choose the line corresponding to the specified shingle. Account for starter material, ridge caps and special accessories separately. If a supplier packages a ridge product with a stated linear coverage, measure the ridge length directly and divide by that package coverage. Keep the packaging label with the takeoff so a change of product can be recalculated without measuring the footprint again.
The shield calculation covers a band along both eaves. Enter its distance up the roof surface, including the overhang, according to the approved roofing detail. Each plane is limited to its full sloped width so that wide bands on a narrow roof cannot count the same deck twice. The order adds the chosen waste allowance and divides by effective coverage per roll. Account for side and end laps when determining that effective coverage. A nominal roll area can exceed the area actually covered after overlapping sheets.
Drip edge runs along two horizontal eaves and four inclined rake edges. The output is the measured linear footage before laps. For an order of stock lengths, mark the corners and transitions on a sketch. Check the lap and cut requirements for the selected profile before rounding up to whole pieces. An offcut from one edge may fit another edge, depending on its length and the direction of the finish.
An attached porch with a different pitch needs its own takeoff. Keep the main roof and porch measurements separate, remove any area that is shared, and combine the unrounded quantities before rounding the order. Measure valleys, dormers and penetrations from their own details. They can add membrane and flashing even where the shingle area changes only slightly. Confirm the shingle manufacturer’s slope and underlayment instructions for the installation, especially at the low end of the pitch selector.
Measure the roof projection to the outside edges, including overhangs.
Enter the eave length parallel to the ridge and the full horizontal span across it.
Use the bundle coverage and effective membrane coverage for the selected products.
Check the approved details for eave protection and low-slope installation.
The roof covers 0.89 squares. With the default allowance, order 3 bundles at three bundles per square. The estimate includes 10% waste.
One square covers 100 square feet of sloped roof surface.
A rectangular gable with equal pitches on both sides. Enter the full horizontal projection once.
Both shingle types start at three bundles per square. Enter the actual rate for either product to compare orders.
The estimate covers a band up each roof plane from both eaves. Valleys, penetrations and additional membrane areas must be measured separately.