During my 30 years as a carpenter, I have framed several hundred complicated roofs, and have read nearly every book on the subject. A particularly good one is The Steel Square, by H.H. Siegele, which uses drawing techniques rather than advanced math to illustrate complex rafter cuts.
I began using these drawing techniques because I wanted to better understand the geometry of roof planes. Not only did these methods help me grasp the way complex roofs fit together, but they also increased my cutting speed — and have been excellent teaching tools to boot.
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