Skip to content
Calcapedia
Print as
Number of problems

In the print window, choose “Save as PDF” as the printer (or print it on paper). Seed 1 rebuilds this exact sheet.

Showing 10 problems, seed 1.

Roof Pitch worksheet

Grades 9–10 · CCSS HSG.SRT.C.8

Solve each problem and show your work. Round answers to 2 decimal places where needed.

  1. Problem 1.
    • I know the: Slope (%)
    • Slope: 50%
    • Also find the rafter length: Yes
    • Building span (wall to wall): 26 ft
    • Eave overhang (horizontal): 2 ft

    Find: Roof pitch

  2. Problem 2.
    • I know the: Angle (degrees)
    • Roof angle: 24 °
    • Also find the rafter length: Yes
    • Building span (wall to wall): 24 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  3. Problem 3.
    • I know the: Angle (degrees)
    • Roof angle: 30 °
    • Also find the rafter length: Yes
    • Building span (wall to wall): 22 ft
    • Eave overhang (horizontal): 2 ft

    Find: Roof pitch

  4. Problem 4.
    • I know the: Angle (degrees)
    • Roof angle: 24 °
    • Also find the rafter length: Yes
    • Building span (wall to wall): 20 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  5. Problem 5.
    • I know the: Slope (%)
    • Slope: 50%
    • Also find the rafter length: Yes
    • Building span (wall to wall): 34 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  6. Problem 6.
    • I know the: Angle (degrees)
    • Roof angle: 40 °
    • Also find the rafter length: Yes
    • Building span (wall to wall): 27 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  7. Problem 7.
    • I know the: Angle (degrees)
    • Roof angle: 30 °
    • Also find the rafter length: Yes
    • Building span (wall to wall): 26 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  8. Problem 8.
    • I know the: Pitch (x in 12)
    • Pitch: rise per 12 of run: 6 /12
    • Also find the rafter length: Yes
    • Building span (wall to wall): 16 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

  9. Problem 9.
    • I know the: Pitch (x in 12)
    • Pitch: rise per 12 of run: 7 /12
    • Also find the rafter length: Yes
    • Building span (wall to wall): 20 ft
    • Eave overhang (horizontal): 2 ft

    Find: Roof pitch

  10. Problem 10.
    • I know the: Pitch (x in 12)
    • Pitch: rise per 12 of run: 7 /12
    • Also find the rafter length: Yes
    • Building span (wall to wall): 16 ft
    • Eave overhang (horizontal): 1 ft

    Find: Roof pitch

Answer key: Roof Pitch worksheet

  1. 1. Roof pitch: 6/12

    1. Find the pitch: a slope percent is the rise per 100 of run, so scale it to a run of 12

      12×50100=6
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 6/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan612=26.5651 °
    4. Find the slope percent: the rise for every 100 of run

      612×100=50 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(612)2=1.118034
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      262=13 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      13×612=6.5 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      13+2×1.118034=16.7705 ft
  2. 2. Roof pitch: 5.34/12

    1. Find the pitch: the tangent of the angle is rise ÷ run, so multiply it by 12 to get the rise per 12 of run

      12×tan24 °=5.3427
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 5.34/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan5.342712=24 °
    4. Find the slope percent: the rise for every 100 of run

      5.342712×100=44.5229 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(5.342712)2=1.094636
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      242=12 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      12×5.342712=5.3427 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      12+1×1.094636=14.2303 ft
  3. 3. Roof pitch: 6.93/12

    1. Find the pitch: the tangent of the angle is rise ÷ run, so multiply it by 12 to get the rise per 12 of run

      12×tan30 °=6.9282
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 6.93/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan6.928212=30 °
    4. Find the slope percent: the rise for every 100 of run

      6.928212×100=57.735 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(6.928212)2=1.154701
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      222=11 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      11×6.928212=6.3509 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      11+2×1.154701=15.0111 ft
  4. 4. Roof pitch: 5.34/12

    1. Find the pitch: the tangent of the angle is rise ÷ run, so multiply it by 12 to get the rise per 12 of run

      12×tan24 °=5.3427
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 5.34/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan5.342712=24 °
    4. Find the slope percent: the rise for every 100 of run

      5.342712×100=44.5229 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(5.342712)2=1.094636
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      202=10 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      10×5.342712=4.4523 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      10+1×1.094636=12.041 ft
  5. 5. Roof pitch: 6/12

    1. Find the pitch: a slope percent is the rise per 100 of run, so scale it to a run of 12

      12×50100=6
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 6/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan612=26.5651 °
    4. Find the slope percent: the rise for every 100 of run

      612×100=50 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(612)2=1.118034
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      342=17 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      17×612=8.5 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      17+1×1.118034=20.1246 ft
  6. 6. Roof pitch: 10.07/12

    1. Find the pitch: the tangent of the angle is rise ÷ run, so multiply it by 12 to get the rise per 12 of run

      12×tan40 °=10.0692
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 10.07/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan10.069212=40 °
    4. Find the slope percent: the rise for every 100 of run

      10.069212×100=83.91 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(10.069212)2=1.305407
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      272=13.5 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      13.5×10.069212=11.3278 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      13.5+1×1.305407=18.9284 ft
  7. 7. Roof pitch: 6.93/12

    1. Find the pitch: the tangent of the angle is rise ÷ run, so multiply it by 12 to get the rise per 12 of run

      12×tan30 °=6.9282
    2. Write the pitch the way roofers do: rise per 12 of run

      pitch = 6.93/12
    3. Find the angle: arctan turns rise ÷ run back into degrees

      arctan6.928212=30 °
    4. Find the slope percent: the rise for every 100 of run

      6.928212×100=57.735 %
    5. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(6.928212)2=1.154701
    6. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      262=13 ft
    7. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      13×6.928212=7.5056 ft
    8. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      13+1×1.154701=16.1658 ft
  8. 8. Roof pitch: 6/12

    1. Write the pitch the way roofers do: rise per 12 of run

      pitch = 6/12
    2. Find the angle: arctan turns rise ÷ run back into degrees

      arctan612=26.5651 °
    3. Find the slope percent: the rise for every 100 of run

      612×100=50 %
    4. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(612)2=1.118034
    5. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      162=8 ft
    6. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      8×612=4 ft
    7. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      8+1×1.118034=10.0623 ft
  9. 9. Roof pitch: 7/12

    1. Write the pitch the way roofers do: rise per 12 of run

      pitch = 7/12
    2. Find the angle: arctan turns rise ÷ run back into degrees

      arctan712=30.2564 °
    3. Find the slope percent: the rise for every 100 of run

      712×100=58.3333 %
    4. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(712)2=1.157704
    5. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      202=10 ft
    6. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      10×712=5.8333 ft
    7. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      10+2×1.157704=13.8924 ft
  10. 10. Roof pitch: 7/12

    1. Write the pitch the way roofers do: rise per 12 of run

      pitch = 7/12
    2. Find the angle: arctan turns rise ÷ run back into degrees

      arctan712=30.2564 °
    3. Find the slope percent: the rise for every 100 of run

      712×100=58.3333 %
    4. Find the pitch factor, the sloped length for each foot of flat run. It also turns flat area into roof area

      1+(712)2=1.157704
    5. Each rafter on a gable roof covers half the span, so halve it to get the rafter run

      162=8 ft
    6. Find how high the ridge sits above the walls: the rafter run times the rise per foot (pitch ÷ 12)

      8×712=4.6667 ft
    7. Add the overhang to the run, then multiply by the pitch factor to get the sloped rafter length

      8+1×1.157704=10.4193 ft