Devers De Pas Rafter Angles



    Devers De Pas Rafter Angles Input variables
  1. Main Roof Pitch Angle
  2. Main Hip Rafter Plan Angle
  3. Devers De Pas Rafter Plan Angle

Calculated Results for the Devers De Pas Rafter Angles

  1. Main Roof Slope Angle
  2. Main Pitch
  3. Main Hip Rafter Plan Angle
  4. Devers De Pas Rafter Plan Angle
  5. Main Hip Rafter Angle
  6. Main Hip Rafter Pitch
  7. Main Hip Rafter Backing Angle
  8. Main Hip Rafter Jack Rafter Side Cut Angle
  9. Main Hip Rafter Sheathing Angle
  10. Devers De Pas Rafter Slope Angle
  11. Devers De Pas Rafter Pitch
  12. Devers De Pas Rafter Peak Miter Angle
  13. Devers De Pas Rafter Peak Bevel Angle
  14. Devers De Pas Rafter Peak Saw Blade Bevel Angle
  15. Devers De Pas Horizontal Plane Rotation Angle
  16. Devers De Pas Vertical Plane Tilt Angle
  17. Devers De Pas Rotated Rafter Slope Angle
  18. Main Hip Rafter Devers De Pas Rafter Housing Angle
  19. Devers De Pas Rafter Foot Level Cut Miter Angle
  20. Devers De Pas Rafter Foot Level Cut Bevel Angle
  21. Devers De Pas Rafter Foot Level Cut Saw Blade Bevel Angle
  22. Devers De Pas Rafter Foot Plumb Peak Miter Angle
  23. Devers De Pas Rafter Foot Plumb Bevel Angle
  24. Devers De Pas Rafter Foot Plumb Saw Blade Bevel Angle
  25. Devers De Pas Rafter Ridge Peak Miter Angle
  26. Devers De Pas Rafter Ridge Bevel Angle
  27. Devers De Pas Rafter Ridge Saw Blade Bevel Angle
  28. Devers De Pas Rafter Crossing Miter Angle
  29. Devers De Pas Rafter Crossing Bevel Angle
  30. Devers De Pas Rafter Crossing Saw Blade Bevel Angle
The Main Hip Rafter Plan Angle can be from 30° to 80° and the Devers De Pas Rafter Plan Angle can be from 30° to 80°. Both angles can be the same. With a hexagonal ground plan you could enter 60° for the Main Hip Rafter Plan Angle and 60° for the Devers De Pas Rafter Plan Angle. The roof framing ground plan view can be anytype of roof framing ground plan. Square, Pentagon, Hexagon, Octagon or Trapezoidal ground plan.
dévers de pas
Simplified




To simplify the DP line geometry I'm using a square rectangle plan with an equal pitched roof slope in this example. The valley rafters that are rotated into the roof surface plane are crossing each other. 


Equal Pitched Roof Slope
8:12 = 33.69007





Develop the hip rafter right triangle BGH. The rise of the roof is 8". Draw GH 8" in length and perpendicular to line BG. Then draw line HB, that represents the true length of the hip rafter.

Next draw the line LD perpendicular to line AB that intersects line BG at D. Then draw the line DF perpendicular to line BG. Line DK is equal in length to DF and is perpendicular to line LD. Draw the line LK. Next draw a line that is perpendicular to line LK.Continue line LD to intersect the line KM . The line KM is the TC line. From E, draw a line to M. The line EM is the DP line, that will establish the rafter's miter and bevel angle.

The line TC is always perpendicular to the roof surface. Laying a framing square on the roof surface from point L thru point D will locate the point M. 




In this next drawing the point P is the intersection of line BG and EM. From point P draw a line to F. Transfer the lines between point F,P,E and D to the side of the drawing to establish the miter angle of the rafter that's rotated into the roof surface plane. We need to establish the point Q and V for the miter angle.




Draw the line DF' perpendicular to line ED, then draw the line EF'. Next strike an arc from center point D the length of DF . Strike an arc from center point E the length of EF'. Where the two arcs intersect , point Q, draw the line QP and EQ. Draw another perpendicular line to EQ that intersects at point P. This will form the line VP. The angle VPQ is the miter angle of the valley rafter rotated into the roof surface plane.


This next drawing shows how to develop the bevel angle of the valley rafter rotated into the roof surface plane. The bevel angle is 2 * the Jack Rafter Side cut Angle.


The geometry shown on this page can be used to develop the dévers de pas,  DP line, for any roof eave angle, like an pentagon (108°), hexagon (120°), octagon (135°) etc... , when the valley rafters are rotated into the roof surface plane.


WorldSkills dévers de pas & trait carré


WorldSkills 2011 Carpentry Competition Model Geometry with dévers de pas & trait carré


Hexagonal Roof Plan with dévers de pas & trait carré


Steps to geometrically develop the Trapezoidal Ground Plan Skewed Rafter on page 52 in "Traité Théorique et Pratique de Charpente" by Louis Mazerolle.