Roof Framing
Metric Rafter With Roof Slope in Degrees
This calculator uses metric measurements to calculate the rafter run and rise, length from top of rafter to the plumb line, overall rafter length, height above the plate (HAP), height of ridge above the top plate, ridge board (beam) support, and to complete the birdsmouth, the length of the heel cut.
Note:
Diagonal length A to B is measured from where the rafter attaches to the ridge board to outside of the wall, the location of your plumb line used for the seat and heel cuts.
Calculation
- enter the width of the building in metres
- the rafter overhang in millimetres
- the pitch of your roof in degrees
- the thickness of your ridge beam or board in millimetres
- the depth of the ridge beam in millimetres
- the actual rafter depth in millimetres (a 2 x 12 is the nominal measurement, actual the 12 is closer to 11 1/4)
- the length of your seat cut in millimetres
Results
- roof pitch, rise in 12
- the run in metres
- the run-in millimetres
- the rise in metres
- the rise in millimetres
- A to B length (length of rafter minus overhang) in metres
- A to B length in millimetres
- length of rafter including overhang in metres
- rafter length in millimetres
- the heel cut length based on the seat cut in millimetres
- the height above plate measurement in millimetres (HAP)
- the ridge height (top of plate to top of the ridge) in metres
- post height (ridge beam support) in metres
- post height in millimetres
Roof Framing
- Birdsmouth Cut, The Heel
- Birdsmouth: Heel Cut, Seat Cut
- Convert a Roof Pitch to an Angle
- Heel Cut of a Birdsmouth
- Height Above Plate (HAP) with Heel Cut Depth
- Height Calculation for a Common Truss
- Rafter Length
- Rafter Length (Metric)
- Rafter Length Calculated in Metres (with rise, run, post height, birdsmouth)
- Rafter Lengths, Hip and Common
- Rafter Length (with rise, run, post height, birdsmouth)
- Roof Measurement
- Roof Pitch
- Roof Sheathing - Gable (Imperial)
- Roof Sheathing - Gable (Metric)
- Roof Sheathing - Hip Roof (Imperial)
- Roof Sheathing - Mansard (Imperial)
- Roof Sheathing - Shed (Imperial)
- Slope, Roof, Hip Valley, Height and Width Factors