Ballarat police have confirmed the fire has been deemed not suspicious.

CFA fire investigators and Ballarat Criminal Investigation Unit detectives checked out the burnt out warehouse on Friday.

An arson chemist was also expected to visit the premises.

UPDATE: 8.20am

The burnt-out shed was used by high profile Ballarat business Adroit Fencing.

The CFA said emergency services were first alerted to the blaze at 12.50am.

Three CFA vehicles and crews responded, along with FRV crews, police and paramedics.

Firefighters wore breathing apparatus to extinguish the blaze before it was deemed under control at 2.04am.

An advice message was issued, warning the community of smoke in the area.

The incident was declared safe at 2.34am before being handed to Ballarat police to maintain security of the site until fire investigators arrived today.

EARLIER:

Police are guarding what's left of a large shed, after a Sebastopol fire that took an hour to bring under control,

The blaze was first reported just before 1am in Hertford Street, near Sutton Street.

Eight fire vehicles turned up - including a ladder platform truck, and others from Ballarat City (FRV station 67), Lucas (FRV station 67) and Sebastopol CFA.

FRV said the 15 by 40 metre shed was fully alight when crews arrived - it's not yet clear what started the blaze.

Police confirmed Ballarat Criminal Investigation Unit detectives are also looking into the circumstances.

The CFA will also send fire investigators this morning.

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