Timber Framing Angle: P7
P7 = Roof sheathing angle, top bevel angle on a purlin rafter, parallel with the eaves line. The included roof angle. Top bevel angle on the stick.
Hip-Valley Roof Ratios Angle Formulas
- P7 = arctan( tan(D) ÷ cos(S))
- P7 = arccos( cos(D) × cos(R1))
- P7 = arcsin( sin(R1) ÷ sin(S))
- P7 = arctan (tan Plan Angle ÷ cos Profile Rafter Slope Angle)
- P7 = arccos (cos Plan Angle × cos Hip Rafter Slope Angle )
- P7 = arccos (tan Backing Angle ÷ tan Profile Rafter Slope Angle)
- P7 = arcsin (sin Plan Angle ÷ cos Backing Angle)
- P7 = arcsin (sin Hip Rafter Slope Angle ÷ sin Profile Rafter Slope Angle)
- P7 = arctan (tan Hip Rafter Slope Angle ÷ sin Backing Angle)
The Hip-Valley Roof Ratios Angle Formulas were developed by Joe Bartok.
The Timber Framing Hawkindale Angle Formulas were developed by Rees Hawkins Acheson from the Martindale Hip and Valley Roof Angles and Hawkindale angle drawings by Ed Levin of the Timber Framers Guild.
The Hawkindale angles were based on the book by Frank L. Martindale "Bevel Angles for Three Dimensional Connections" 1948 that was based on the book
"Hip and Valley Design" by H. L. McKibben and L. E. Gray published in 1912.