## Wednesday, January 14, 2015

### Ancient Knowledge Task Model #1

I finally finished the task model study from Bernd Kuppers book "The new Book on the Ancient Knowledge of Roof Framing". I learned a lot from this task model study. Without Bernd's book it would have probably taken a year or two to research the geometry that defines the geometric layout of this task model.

Key Notes:

1. Rising Purlin Seat Cut Layout.
2. Hip Rafter King Post.
3. Knee Brace bevel cut layout.
4. Shadow Line technique for laying out the intersection of canted roof planes.
5. Developing the geometric layout for the plumb cut on the canted rafter tails.
6. Developing the geometric layout for the folding roof surface for the seat cuts on the rising purlin.
7. Developing the geometric layout for the bevel cut on the end of the rising purlin following the canted hip rafter.
8. Developing the geometric layout for the bevel cut for the plumb hip rafter to canted hip rafter.
9. Developing the geometric layout for the sloping ridge of the dormer.
10. Developing the geometric layout for the folding roof surface plane of the sloping dormer.
11. Developing the geometric layout for the jack rafter claws for the plumb hip rafter.
12. Developing the geometric layout for the jack rafter claws for the canted hip rafter.
13. Developing the geometric layout for the claw of the dormer gable rafter for the two canted hip rafters
14. Developing the geometric layout for the jack rafter claws for the second dormer jack rafter that intersects two canted hip rafters.
15. The jack rafters on the sloping ridge dormer are at an angle of 90° to the sloping ridge. However, they are canted to the eave line of the dormer profile rafter. The jack rafters Shadow line are also at 90° to the sloping ridge line in plan view. Since the sloping ridge is actually a hip rafter, the jack rafters shadow line is also the line that defines the dihedral angle of the hip rafter.