City of Chicago - Permits and Renovation Requirements

[Tracey Steele]

Hi BP Community - I'm exploring purchasing a property that has no existing city violations. I would like to add a room, which includes framing out a couple walls and adding outlets. I know this work will require a permit. 

The home was last upgraded in the late 1990s/early 2000s, so I suspect building code has changed between now and then. Am I required to upgrade the entire home to current building code (e.g., upgrade electrical or plumbing, if needed) or just the new room?

Thanks!