The mayor made the announcement Thursday alongside members of a condominium conversion task force on the city's Northwest Side.
The mayor says that while condo conversions increase stability and investment in neighborhoods, they sometimes displace existing tenants who can't afford to buy.
Among other restrictions, the new ordinance would increase the required tenant notice period from 4 months to 9 months. And it would require landlords to give renters at least $1,500 to relocate if their building converts.
Daley said the proposal will be key when the city's market for condominiums begins to rebound.