lou-800CityClubApartmentsrooftopLouisville (2) City Club Apartments in Louisville (foreground) has helped bring back luxury apartment living to the downtown.

LOUISVILLE—The rising rents in many of the nation’s gateway markets, along with escalating construction and labor costs, have led many firms to seek out less expensive spaces in secondary cities. And according to first quarter research from CBRE, the Louisville office market’s overall asking rental rate is the second lowest in the nation.