A CBD apartment building hit by fire on New Year's Eve is one of the many Melbourne buildings known to harbour illegal rooming houses, with living rooms rented to multiple tenants as sleeping spaces.
But a City of Melbourne building surveyor who inspected the apartment where the fire broke out said there was no evidence that particular flat was overcrowded.
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Apartment blaze shuts down Spencer St
RAW VIDEO: North-west of Spencer St is blocked off after firefighters rush to battle a blaze on the upper floors of an apartment directly opposite Southern Cross station.
More than 27 firefighters from 12 fire trucks battled the blaze on the 29th floor of 200 Spencer Street, opposite Southern Cross Station.
MFB crews managed to contain the fire to an air conditioner on a balcony before bringing it under control. Firefighters received a report of the blaze at 1.48pm.
A police spokeswoman said there were no suspicious circumstances.
One resident, who lives six floors above the affected unit, said the apartment building was continually "full" with people. It's understood the building is meant to house 1200 people and is consistently at or above capacity.
The City of Melbourne has cracked down on "sophisticated" illegal rooming house networks in recent months, hiring a professional investigator to gather evidence against unscrupulous operators.
Fairfax has previously exposed growing evidence that city apartments are being crowded with foreign workers, students and backpackers, who are charged excessive rent for tiny sleeping quarters including partitioned living rooms.
While the apartment that caught on fire was not being run as an illegal rooming house, Fairfax is aware of other apartments in the building being used in this way.
One advertisement on Gumtree calls for a "female" to share a living room in a two-bedroom apartment at 200 Spencer Street with a "Korean girl" for $130 a week, plus $300 bond.
Fairfax rang the woman who posted the advertisement, who told Fairfax there were currently six people living in the apartment. She then passed the phone to another person who disconnected the call.
A student who recently found an illegal rooming house at 200 Spencer Street through Airbnb told Fairfax: "The [landlord] is a young Taiwanese woman who has over 30 apartments that she sublets."
The apartment was shared with up to eight tenants, including a woman nominated as a manager by the landlady, who slept in a corridor just big enough to squeeze in a single mattress.
"A note in English and Chinese points out that any fire that [requires the fire brigade] and incurs fees are to be paid by the tenants. The girls are very afraid of this and often cook with the doors open," the woman said.
"What amazes me is the extent of such a huge black economy, firmly entrenched within the city, and part and parcel of the whole business of the international student industry," she said.
"The landlord uses different names and accounts, and as every tenant pays on an individual basis, how can anything be tracked?"
A house or apartment that is being sublet to four people or more is considered to be an illegal rooming house.
A resident at 200 Spencer Street who had been evacuated during the fire said some residents regularly flicked cigarette butts off their balconies, and speculated that a carelessly discarded cigarette may have contributed the fire.
The apartment block is less than 10 years old, having been completed in late 2007, according to commercial property information service Cityscope.
The 43-storey building has 372 apartments and eight levels of car parking.
One resident who was waiting to return home said "quite a few" international students lived in the building.
A City of Melbourne spokesman urged anyone with evidence of a suspected illegal rooming house to contact the council with details.
With Anna Whitelaw