1. The extension is for a small covered terrace. The main load will be the wind load.
2. The added piece is 8'long.
3. Lateral support is provided by the roof deck.
4. The splice occurs at the end of the main rafter, sticking out of the outside wall.
I would like to know how to extend a 2"x6" southern pine wood rafter so that it keeps the same structural properties as if it was a continous member. Will a 4' overlap an two 1/2" bolts suffice? How is this calculated?