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I'm making a lean to greenhouse. The highest wall is 97 1/8" high. The outside wall (low eve) is 84" high. Adjusted run is 98". I want my pitch at 2:12 but I can't get the speed square to pivot to 2" on a 2x4 rafter. Giving the height of the 2 walls, what should the pitch be? And if I can keep the 2' pitch, what would be the angle of the plumb cut?

I bought a construction calculator because the math involved was making my head spin.

Jim

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If one wall is 8' high (or close) and the other wall is 7' high, and there's 8' (or close) in between them, then the pitch is going to be 1 1/2:12.

I came up with 7 degrees for the plumb cut (or 83 degrees, depending on what you measure from).

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(05-22-2020, 01:09 PM)DieselDennis Wrote: If one wall is 8' high (or close) and the other wall is 7' high, and there's 8' (or close) in between them, then the pitch is going to be 1 1/2:12.

I came up with 7 degrees for the plumb cut (or 83 degrees, depending on what you measure from).

Thank you sir. I also came up with 1 1/2:12 pitch but rounded up to 2 thinking it would simplify things.

Jim

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Yeah, your back wall should be 100 5/16" for a 2:12. Plumb cut is 9.46*

"This is our chance, this our lives, this is our planet we're standing on. Use your choice, use your voice, you can save our tomorrows now." - eV

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