Old factory buildings are being illegally converted into subdivided housing - and the trend is on the rise.
Each of the city's older factory areas - such as Kwun Tong, Tai Kok Tsui and San Po Kong - hold at least 10 to 20 such buildings and many are dangerous, according to the Society for Community Organisation (Soco).
But officials said their hands were tied as they had difficulty getting into private premises to conduct checks.
Soco said it had seen an increase in the number of illegally subdivided factories in the past two to three years, and expected more as rents continued to soar and public housing supply remained inadequate.
'[Factory-turned illegal housing] is even cheaper than subdivided flats in old residential buildings. But many of them are even more dangerous,' said Soco organiser Chan Siu-ming, who works on problems arising from subdivided flats.
He said there was an increase in demand for these tiny dwellings, but the supply was declining as many old buildings converted into subdivided flats were being demolished for redevelopment.