## Sunday, February 10, 2013

### World Skills International Competition Roof

After looking at a couple of Joe Bartok's cardboard roof models yesterday it gave me an idea for a roof that could be used in the World Skills International Competition  in Europe. This World Skills International Competition Roof  would have an hexagonal foot print with an star foot print extending from two sides.

This  hexagonal  roof has hip rafters that are both a hip and a valley rafter at the same time. It also would have one roof slope angle that can only be calculated from the geometry of the roof. In my example  I've used an 5:12 pitch as the main roof pitch with the adjacent hexagonal eave angle having an 12:12 roof pitch.

If the World Skills International Competition judges are expecting perfect cuts from the competitors, then maybe they could use my Rafter Tools apps to check the accuracy of the  competitors geometry. I tested my new and improved plan angle formula on this hexagonal roof and it returned the correct plan angles for the 3 different roof pitch angles with the 3 different eave angles.

Just found these drawing for the World Skills International Competition in 2010 & 2011. The drawing is showing a roof with the purlin rafter projecting under the hip rafter. The student would have to know how to geometrically draw out the purlin lip cut angle. The World Skills International Competition allows carpenters to use calculators. Maybe the World Skills International Competitors could use the Rafter Tools calculator?

Here are a couple of drawings showing how to draw out the purlin lip cut angle.

1. That's cool! In my opinion, future roofers out there should build a fondness for geometry if they want to succeed in the field, as this subject is the foundation of measuring, shaping and framing height and width.

Joanne Barragan

2. The application of geometrical figures in the roof makes me think of the advancement of the roofing industry. I know that engineers and architects are using mathematical formula and shapes in their designs, but it looks so good to have all those geometrical figures in reality. I bet the homeowner that’ll use this design will be one happy homeowner. :)

-Julio Wells-

3. I find geometry in roofing critical for this plays an important role in determining the degree of wind resistance and calculations in terms of load-bearing elements. Geometry, from an architect's point of view, is practical in aesthetic and structural, or functional, considerations.

ABC Roofing Inc.

4. ABC Roofing Inc
ABC Roofing Inc
http://www.ncroofingcontractor.com/
ABC Roofing has been consistently ranked as one of Greensboro’s most trustworthy roofers since 2006. We install roofing, siding, gutters, skylights, decks, windows, and sunrooms. We can tackle ventilation issues, flashing problems, and chimney repairs as well. We’ve made sure that we’re proficient in installing all roof types, which means when you call us you get access to all the roofing options, including asphalt, wood, fiberglass, metal, or tile.

5. ABC Roofing Inc
ABC Roofing Inc
http://www.ncroofingcontractor.com/
ABC Roofing has been consistently ranked as one of Greensboro’s most trustworthy roofers since 2006. We install roofing, siding, gutters, skylights, decks, windows, and sunrooms. We can tackle ventilation issues, flashing problems, and chimney repairs as well. We’ve made sure that we’re proficient in installing all roof types, which means when you call us you get access to all the roofing options, including asphalt, wood, fiberglass, metal, or tile.

6. I was reading your article and wondered if you had considered creating an ebook on this subject. Your writing would sell it fast. You have a lot of writing talent.
Certified Precision Roofing