Why are there external patches on internal surfaces?

[ktsdesigner]

Apologies if this has been covered elsewhere, but I wondered if there is something I'm missing. As per the FAQ article, I understand why this happens, but how do I either avoid it, or fix it?

Is it as basic as hand deleting/modifying the geometry in ModelIT or ripping the architects drawing up and redrawing all inner partitions as single lines in AutoCAD before importing?


http://www.iesve.com/support/knowledgebase/faq/2310