Roof Framing Angles: Sample Values
Major Pitch = 10 ÷ 12         Minor Pitch = 8-1/2 ÷ 12
W = 135° , angle viewed in plan between Hip eaves or Valley ridges
Rises are based on a Run = 12"
Definitions Formulas Diagrams
Framing and Joinery Angle Calculator
 Common Rafter Pitch Angle or Common Rafter Plumb Cut Angle SS : Major Side Angle = 39.80557° S : Minor Side Angle = 35.31121° The initial values of Pitch Angles are generally given as Over 12 Plan Angle or Deck Angle DD : Major Side Angle = 56.42456° Major Side Rise = 18-3/32" D : Minor Side Angle = 78.57544° Minor Side Rise = 59-3/8" Hip-Valley Rafter Pitch Angle or Hip-Valley Rafter Plumb Cut Angle R1 : Angle = 34.77220° Rise = 8-11/32" Jack Rafter Side Cut Angle P2m : Major Side Angle = 27.01842° Major Side Rise = 6-1/8" P2a : Minor Side Angle = 9.36400° Minor Side Rise = 1-31/32" Sheathing Angle 90° - P2m : Major Side Angle = 62.98158° Major Side Rise = 23-17/32" 90° - P2a : Minor Side Angle = 80.63600° Minor Side Rise = 72-25/32" Backing Angle C5m : Major Side Angle = 20.73487° Major Side Rise = 4-17/32" C5a : Minor Side Angle = 6.57434° Minor Side Rise = 1-3/8" Plumb Backing Angle A7m : Major Side Angle = 24.74318° Major Side Rise = 5-17/32" A7a : Minor Side Angle = 7.98675° Minor Side Rise = 1-11/16" Hip-Valley Rafter Side Cut Angle at the Hip Rafter foot or Valley Rafter peak R4Bm : Major Side Angle = 51.05890° Major Side Rise = 14-27/32" R4Ba : Minor Side Angle = 76.17896° Minor Side Rise = 48-25/32" Saw Blade Bevel Angle along the Hip-Valley Rafter Side Cut Angle at the Hip Rafter foot or Valley Rafter peak A5Bm : Major Side Angle = 28.36995° Major Side Rise = 6-15/32" A5Ba : Minor Side Angle = 33.98771° Minor Side Rise = 8-3/32" Hip-Valley Rafter Side Cut Angle at the Hip Rafter peak or Valley Rafter foot R4Pm : Major Side Angle = 28.60128° Major Side Rise = 6-17/32" R4Pa : Minor Side Angle = 9.42488° Minor Side Rise = 2-0/32" Saw Blade Bevel Angle along the Hip-Valley Rafter Side Cut Angle at the Hip Rafter peak or Valley Rafter foot A5Pm : Major Side Angle = 18.38520° Major Side Rise = 4-0/32" A5Pa : Minor Side Angle = 6.48636° Minor Side Rise = 1-3/8" Purlin Saw Miter Angle or Bird-Block Saw Miter Angle P1m : Major Side Angle = 23.02268° Major Side Rise = 5-3/32" P1a : Minor Side Angle = 6.66234° Minor Side Rise = 1-13/32" Purlin Saw Blade Bevel Angle or Bird-Block Saw Blade Bevel Angle Square Cut Fascia Saw Blade Bevel Angle on the Hip-Valley Rafter C1m : Major Side Angle = 25.14135° Major Side Rise = 5-5/8" C1a : Minor Side Angle = 9.30188° Minor Side Rise = 1-31/32" Square Cut Fascia Saw Miter Angle on the Hip-Valley Rafter Angle on the Hip-Valley Rafter Purlin or Bird-Block intercepts Hip-Valley Rafter R2m : Major Side Angle = 10.23382° Major Side Rise = 2-5/32" R2a : Minor Side Angle = 1.08163° Minor Side Rise = 0-7/32"