A massive fire has engulfed the head office and factory outlet of a Sydney furniture company, sending black smoke billowing into the sky and brick walls tumbling to the ground.

The industrial fire on Beresford Avenue at Greenacre took hold about 3pm on Tuesday, and while it had been contained by about 6pm, the fire is expected to smoulder for some time.

The fire took hold about 3pm on Tuesday.

The fire took hold about 3pm on Tuesday.Credit: Nine News

More than 60 firefighters battled the blaze, breaking into nearby businesses in a bid to stop the fire spreading.

Water supply had been a problem, Fire and Rescue NSW Superintendent Adam Dewberry said.

“One of the complexities of this particular operation was, not only the fuel loading, being the furniture and timber … was the difficulty in getting significant water up into the fire trucks.

“Fire and Rescue NSW had to … pump water from a distance in other streets off other big mains to get enough water on to the fire,” Dewberry said.

An exclusion zone was set up by NSW Police, who urged people to avoid the area. Residents and workers nearby were advised to close doors and windows.