The recent bad weather could be to blame for a 14% drop in the number of new homes and extensions being built.
The national housing construction index also found a 3% fall in planning applications made between January and February compared with last year.
Data showed commencement notices, which record when a building project starts, rose in five counties including Dublin, where there was a 17% rise.
There were 624 new builds at the start of 2013 nationwide, compared with 726 a year earlier.
Danny O'Shea, of Link2Plans, which issued the figures, said the largest growth was in Monaghan (20%), Mayo (60%) and Roscommon (78%), while some counties plunged below the national average including Westmeath (-79%), Waterford (-55%) and Cavan (-52%).
But he did not see the falls as cause for alarm.
"In the January/February analysis period, I believe that a key factor at play was the bad weather, explaining why many projects have yet to get off the ground," he said.
Elsewhere he said the outlook is positive despite the decline in planning applications from 1,707 in early 2012 to 1,664.
"Offaly, Limerick and Wexford exhibit the largest percentage application drop, but with increases in eleven countries, the outlook for coming months is potentially positive," he added.