Construction’s unemployment rate rose in December to 13.5%, from November’s 12.2%, even with an industry gain of 30,000 jobs last month, the Bureau of Labor Statistics reported.

The latest monthly BLS employment report, released on Jan. 4, also showed that construction’s jobless rate last month was down from the December 2011 figure of 16.0%. December marked the 27th straight month in which construction posted year-over-year improvement in its unemployment rates.

The BLS rates are not adjusted to reflect seasonal swings. In the highly seasonal construction industry, cold-weather months tend to show a drop in the volume of projects in much of the country and a rise in the jobless rate.

The pickup of construction jobs last month came almost across the board among construction industry segments.  Specialty trade contractors led the way, with a gain of 17,900 jobs. Buildings construction added 12,800 jobs. The only sector to record a decline was heavy/civil construction, which lost 700 positions.

The architectural and engineering services sector, a separate BLS industry category, also was on the upswing, gaining 3,800 jobs in December.

Ken Simonson, Associated General Contractors of America chief economist, said, “Resurgent demand for new housing construction and modest growth in private commercial construction are helping crate some new construction jobs.” He added, “Now that the threat of the fiscal cliff has been—temporarily—relieved, construction unemployment should continue to slowly rise in 2013.”

Simonson and Anirban Basu, Associated Builders and Contractors chief economist, note that total construction employment is up by only 18,000, or 0.3%, over the past 12 months—an indication that many workers have left the industry through retirement, shifting to other fields or returning to school.

Basu also said it is possible that a significant portion of the December construction-jobs gain stemmed from the start of post-Hurricane Sandy rebuilding in New York, New Jersey and other states hit hardest by the massive late-October storm.

Basu added, “With additional relief monies expected to pour into communities affected by Hurricane Sandy, further rebuilding-related construction employment growth is expected.”

BLS releases later this month on metropolitan area, state-by-state and regional unemployment rates should shed more light on the post-Sandy construction jobs impact.

More broadly, BLS said the national unemployment rate held at 7.8% in December, the same as November’s level, as the economy added 155,000 jobs.