PITCH TABLES

Pitch tables

Copy the appropriate table onto a hard piece of cardboard and place it into your tool belt for handy reference on the job.

To find an unknown dimension given a known dimension, multiply the known value by the tabulated factor appearing on the same line where the known factor is shown as one.

Example: For a 4:12 pitch, what is the slope distance given the vertical distance? From the table, find the line with “1” for the vertical, and multiply the known distance by 3.162 for the slope distance.

The angles shown are for jack rafters framed into a hip, with Tilt angle corresponding to the plumb cut, and Miter angle corresponding to the face cut. These angles assume the saw is indexed at Zero degrees on the table and 90 degrees on the miter gauge. If not, subtract the given value from 90 degrees for the correct saw angle setting.

Pitch 2 : 12 = 9.46^o, Hip length = 17.088” / ft. of common horizontal run.
Horizontal.....Vertical.....Slope
....1.................0.1667......1.014
....6.................1................6.083
....0.9864.......0.1644.......1
Difference in lengths of Jacks, 16” C-C = 16.221”, For Hips, Miter 44.5^o, Tilt 9.5^o

Pitch 4 : 12 = 18.435^o, Hip = 17.436” / ft. of common horizontal run.
Horizontal.....Vertical.....Slope
....1.................1/3.............1.054
....3.................1.................3.162
....0.949.......0.316............1
Diff. Jacks = 16.866”, Miter 43.5^o, Tilt 18.5^o

Pitch 6 : 12 = 26.56^o, Hip = 18.00” / ft. of common horizontal run.
Horizontal.....Vertical.....Slope
....1.................0.5..............1.118
....2.................1.................2.236
....0.8945......0.447...........1
Diff. Jacks = 17.889”, Miter 41 3/4^o, Tilt 26.5^o

Pitch 8 : 12 = 33.69^o, Hip = 18.762” / ft. of common horizontal run.
Horizontal.....Vertical.....Slope
....1.................2/3..............1.202
....1.5...............1.................1.803
....0.832.........0.555...........1
Diff. Jacks = 19.23”, Miter 39 3/4^o, Tilt 33 2/3^o