Zig-zagging left and right through a maze of dark, narrow corridors in a high-rise’s basement, 35-year-old kitchen worker Hu has joined the many thousands of Chinese fleeing fast-rising property prices by heading down – down underground.

Hu lives here beneath an affluent downtown apartment building, in a windowless, four square-metre apartment with his wife. For 400 yuan ($65.85) a month in rent, there’s no air-conditioning, the only suggestion of heat is a pipe snaking through to deliver gas to the apartments above and the bathroom is a fetid, shared toilet down the hall.

If you have to ask, you can’t afford it

“I can’t afford to rent a house,” said Hu as he showed off his meagre appointments. Living in basement apartments isn’t illegal in China, but like anywhere else it is nothing to brag about and Hu, who guts fish for 2,500 yuan a month at a popular Sichuanese hotpot restaurant on the street above, declined to provide his given name. “If I weren’t trying to save money, I wouldn’t live here,” he said.

Locals have dubbed Hu and his fellow subterranean denizens the “rat race” – casualties and simultaneously emblems of a housing market beyond the government’s control.

Despite efforts to discourage property speculation and develop affordable housing, a steady stream of job-seekers from the countryside and a lack of attractive investment alternatives have kept prices soaring.

Residential property prices rose 10 per cent in November from the same month of 2012, according to data released last week, and have been setting new records every year since 2009. Prices in Beijing are rising even faster – 16 per cent a year – with rents climbing 12 per cent a year.

That’s pushing more and more newly arrived urbanites underground. Of the estimated 7.7 million migrants living in Beijing, nearly a fifth live at their workplace or underground, according to the state news agency.

Beijing’s housing authority refuted this statistic, saying in an email to Reuters that a government survey last year found only about 280,000 migrants living in basements and that only a small percentage of Beijing’s basements were being used as dwellings. Last month, authorities sealed Beijing’s manhole covers after local media discovered a group of people living in the sewers below, with one, a 52-year-old car washer, reported by the local media to have been living there for at least a decade. The sewer dwellers were relocated and those not from Beijing sent back home.

Surging residential prices are both boon and bane to the government. China’s booming property sector accounts for roughly 15 per cent of GDP and heavily indebted local governments rely on land sales – selling land earns them roughly three times what they collect from taxes.

But rising prices are putting home ownership farther out of reach for most Chinese, worsening the gap between rich and poor and breeding social discontent.

“Some people can buy several homes, some people can’t even buy one,” said Mao Yushi, co-founder and honorary president at the Unirule Institute of Economics, an independent think tank in Beijing. “There will be an impact on society.”