hello (sorry for re-write again)
I actually was trying to make a script to reinforce floor opening but it seems a bit harder than I thought however I have made this graph using data shape to select the element host and after select faces, but it seems I am having a problem in Curve.Normal I hope if you have time to take a look and give me some advice on how to continue to make U shape as in the picture 
Hello, Iām making a similar script and was hoping to see some working examples.
Have you managed to get it working?