Oahu’s office space vacancy rate rose in the third quarter, according to a preliminary report that suggests a recovery may be further off than previously anticipated.

The report by local commercial real estate firm Colliers Monroe Friedlander said 127,606 square feet of office space — the rough equivalent of a 12-story office building — was emptied during the quarter.

This weak activity in the third quarter followed relatively light vacancy growth of 26,043 square feet during the first half of the year.

"Last quarter was a big jump," said Mike Hamasu, research and consulting director for Colliers.

Hamasu said the jump was a surprise. Earlier this year, Colliers had projected that office leasing would begin to strengthen over the next few quarters, setting up the market for positive leasing activity and an improved vacancy rate next year.

Now Colliers projects the vacancy rate will climb next year to extend a market decline into a sixth year.

The report said Oahu has experienced relatively little job growth, which is the principal driver of office space demand. Furthermore, job gains have been largely in business sectors that don’t directly or indirectly boost office leasing.

"Colliers projects that a continuation in office job growth remains tenuous and vulnerable to declines in business optimism and confidence," the report said.

Oahu’s office vacancy rate in the third quarter was 12.9 percent. That is up from 11.8 percent at the end of last year, but is still below a decade high of 13.6 percent in 2002.

The vacancy rate in the third quarter represents 2 million square feet of empty office space out of 15.6 million square feet of inventory.

Higher vacancies have put pressure on rental rates, but not by much, the report said. The average monthly rent for space sought by landlords was $2.80 per square foot in the third quarter. That rate, which includes operating expense charges, is up from $2.74 at the end of last year. However, Colliers said rental rates for new leases signed by tenants are heading down.