Nottinghamshire Fire and Rescue described the incident as “a hugely demanding and resource intensive fire”.
The blaze broke out around 2pm on Monday at the former Player’s cigarette factory in Player Street, Radford.
Fire crews were still tackling the flames overnight on the site where the old factory is being turned into student accommodation.
The Nottinghamshire brigade was assisted by other local fire crews as they worked last night and into the morning.
Structural engineers were also on site to assess the stability of exposed walls on the job.
It is believed high winds have hampered the operation as sections of the roof and floors within the building collapsed.