Do I need permits for this work?

[JD Mims]

Hi all!  I need help with clarification on permits in Cleveland Ohio.

I bought a duplex and replaced electrical panels and turned attic space into additional bedrooms.  

My general contractor says I don't need permits because these are minor alterations..and he's never pulled permits for these things..can anyone give any feedback?  

Tried calling the city but no one answers, sent them an email but was hoping someone here might have helpful information.  Thanks.