R Value Averages
(sorry about crude sketch) Having trouble finding a resource that answers this as most R/U value references deal with calculating sections with different components, etc. If you have an elevation (above) with the different areas having different R values how do you calculate the average R value for the entire elevation? Im assuming you will be given all the R values and dimensions to calculate areas, etc.
Thanks!

I think you would be given the R values and Dimensions as you would think, then you could take the weighted average to find the overall U value. This is off the top of my head, so I could be wrong. You could say this wall is 100SF, with areas 1=25SF, 2=70SF and 3=5SF, then plug each R value in as percentages of the whole to find the weighted RValue. Then "1/Weighted RValue" should give you the U value of the wall in total.
Hopefully someone can chime in and let me know if I'm off base. I just googled this and found worksheets like this.

has this been resolved? both of these equations create wildly different answers. This website implies the second equation is correct.
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