Is renting rooms in condo buildings illegal in Chicago?

There is some confusion in our HOA regarding renting of rooms. We have a leasing restriction & this owner continually states that he is exempt from providing a lease as he rents to another male. We have a leasing restriction in place (2 of 6 units) & he places us at the 50% mark which means no one else can sell or refinance. We're not clear on the Chicago housing ordinance, but we think that renting of rooms is illegal in Condo buildings.