Centroids of Exterior and Interior walls

Pretty new to Revit and Dynamo. I have a few sample Revit models. I am trying to use Dynamo nodes and extract the centroids of Exterior walls and centroids of Interior walls as two seperate lists. I followed several procedures I found on here from experts, but still unsuccessful. Any help is greatly appreciated.

Thank you.

Hi @ferozahmed89

Welcome to Dynamo Forum!

This has been discussed previously on forum. You could search on forum search bar you will find many topics: