New regulations reworking a government-backed housing fund were unveiled Tuesday in Shanghai, making it easier for low-income families in the municipality to get mortgages for affordable housing.

This is the first move to incorporate low-cost apartments, which are subsidized by the government, into the public housing fund.

The Chinese housing fund is similar to a social security program in which employees put a portion of their salary into a reserve that can only be used for housing purchases.

The new guidelines now allow for multiple borrowers to pool their funds and repay loans of one unit together.

The qualified co-borrowers are expanded from spouses or immediate family members who applying for the same units, to any person who also own the property rights, according to the mu-nicipal government's new plan.

"If the borrowers have difficulties in repaying the credit loans, they can apply with the Shanghai Housing Fund Management Center to add more supplementary family members to help them repay the loans using their own housing funds," said the plan.

"Allowing more family members to repay the loans could relieve the stress of property holders who have lower income in the city," said Li Zhanjun, a department head at the E-house China R&D Institute, a real estate research company.

According to Shanghai's affordable housing guidelines, only families with incomes of less than 2,300 yuan ($338.33) per month on average can apply for the residences.

That hurts buyers over 30 who want to buy small apartments.

If an individual with a salary of 2,300 yuan ($338.33) per month wants to buy an apartment with the average sales price of 5,000 yuan ($735.50) per square meter in Minhang district in Shanghai it is difficult for him to repay 1,300 yuan ($191.10) per month for 20 consecutive years.

"Those purchasing affordable houses using the fund have to make a down payment equal to no less than 20 percent of the property's value," the guidelines said.

"And the credit lines for each family will be no more than 600,000 yuan ($88,265)," said the guidelines.

The first batch of affordable houses will be made available in July.