SHANGHAI - China Construction Bank (CCB) said it plans to set up a 30-billion-yuan ($4-billion) fund to finance rental housing, China's latest state-backed effort to aid the struggling property sector.

The state-owned lender, which will provide money for the fund, plans to invest in real estate projects and turn them into affordable rental houses, CCB said in a statement late on Friday.

Beijing has been stepping up efforts to aid a real estate sector hit by debt buildup, mortgage boycotts and sluggish sales. Property and related sectors such as construction account for more than a quarter of China's economy.

The authorities have allowed affordable rental houses to be listed in the form of real estate investment trusts (REITs), opening a fresh financing channel for the business.

Reuters reported in July that China planned to launch a real estate fund to help property developers resolve a crippling debt crisis. The fund would initially be set at 80 billion yuan through support from China's central bank, with CCB contributing 50 billion yuan, a source said.

China's policy banks and local governments have also been setting up funds to help cash-strapped developers finish construction of pre-sold properties, as protests by home buyers spread.

(Reporting by Jason Xue and Brenda Goh; Editing by William Mallard)