The pace of growth in the construction sector slowed down again in the month of August, with slower rises in both activity and new orders evident.
The Ulster Bank Construction Purchasing Managers' Index posted a reading of 55.1 in August, down from 56.6 in July.
August was the third consecutive month in which the pace of growth slowed and the reading was the lowest since March 2015.
Housing was the best-performing sector in August, with companies registering a sharp monthly rise in activity.
Activity on commercial projects continued to rise, but at a reduced pace.
But civil engineering activity declined for the third month in a row.
This indicated that infrastructure, or capital spending, projects are suffering the most pronounced fall off in activity.
"While the overall story remains one of continuing construction sector expansion, the latest PMI readings suggest that momentum behind the recovery has slipped a little - a trend that bears watching in the months ahead," commented Ulster Bank's chief economist Simon Barry.
But he said he was not overly concerned about near-term prospects for the industry because of "the very healthy pattern" of new orders that remained very much in place.
The new orders index again showed strong growth in new business levels in August.
"And these gains in actual and prospective activity continue to underpin rapidly-rising demand for labour within the sector, with the employment index quickening for the second month running in August," the economist said.
The August survey also featured an update of a special question ran at the same time last year regarding firms' views about the possible impact of Brexit.
"As was the case last year, two-thirds of firms see no change in activity over the coming year as a result of Brexit, with broadly similar proportions of respondents expecting activity to be boosted or reduced over the next 12 months," Mr Barry said.
The Government announced plans late last week to ramp up the building of social housing units.
It came as the Central Bank Governor Philip Lane warned that too rapid an expansion of house-building could destabilise the economy.