It is a bit hard without seeing the actual file.
Is there any point at which the pen weight is correct - for example the original section?
If yes then I would say your pen set is being changed in the view settings or a Graphic Override is being used.
If no then the building material setting must be using the wrong fill pen.
Make sure you have no Graphic Overrides in play (or possibly even renovation filters).
Barry.
One of the forum moderators.
Versions 6.5 to 27
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