How do you create wall assemblies in OpenStudio? I understand where the buttons are and how to ultimately create an assembly, just not sure the best way to go about it. I am doing a very large building, so should I just create a general wall assembly for the larger portions of the building and assume they are uniform throughout those sections? Or is it a general practice to go through every wall assembly and create each wall individually. I understand one way is just more accurate, just wondering what people do in general. Also, if there is a material not found in the "Library" and I need to add a material, is there a good place to find the thermal conductivity, resistance, smoothness, etc...? Thank you.