(Reuters) - U.S. retail mall vacancies rose to 8.3 percent in the third quarter, compared with the preceding quarter, due to confirmed closings of J C Penney (JCP.N) and Sears Holdings Corp (SHLD.O) stores, real estate research firm Reis Inc (REIS.O) said.

Construction activity fell 49.2 percent in the quarter, with 1.63 million square feet of new construction completed, the lowest level of completions since 2014, according to the report.
The trend would likely continue as more stores announced bankruptcy or closures, including Toys R Us, The Gap, Teavana and True Religion Jeans, the firm said.

So far, 10 retailers have filed for bankruptcy in 2017, higher than last year, with the number set to eclipse 20 bankruptcies filed during the 2008 financial crisis, according to AlixPartners, which advises distressed firms.
Asking rent inched up 0.4 percent, while effective rent rose 0.5 percent, Reis said.

Net absorption, which is measured in terms of available retail space sold in the market during a certain time period, was at 578,000 square feet in the quarter, the lowest since 2010.
The national vacancy rate for neighborhood and community shopping centers was flat at 10 percent.