2011 London Dormer #2

Still haven't developed the jack rafter perpendicular to the roof surface, but these drawings are a start in the right direction. They develop the sloping dormer profile slope angle.

Keywords to search with in German
Schifter und Wechsel, im rechten Winkel zur Dachfläche.
gauben profil kehlbohenschifter

Ground Plan for the Kehlbohenschifter (Valley Jack Rafter)

Ground Plan, Elevation and GaubenProfil (Dormer Profile) for the Kehlbohenschifter

 Another way of developing the sloping ridge dormer profile slope angle.

The sloping ridge is technically a hip rafter, so we can develop the dihedral angle triangle, the angle between the two planes. This gives us the sloping ridge backing angle.