Here’s a document with the object in question: bbox.3dm (228.3 KB)
The Breps in this case are approximate models of buildings; we’re generating bounding boxes to find their heights, from which we calculate their floor counts, which we in turn use to generate previews of the buildings’ windows. Since it’s just for giving users a rough visual representation, they never needed to be too accurate, so I was using the inaccurate versions. (If there’s a way to do this that doesn’t use bounding boxes that would be totally fine, but I figured a fast bounding box would be a good way to get what we need.)