The number of new buildings fell by 23% in the first six months of 2012 compared to the same time last year, the latest GeoDirectory figures show.
GeoDirectory said the total number of new residential and commercial buildings built nationwide in the first half of the year was 5,620 compared to 7,330 the same time last year.
The figures show a 94% decrease from the peak in 2007, when GeoDirectory identified 60,781 new commercial and residential buildings.
GeoDirectory, jointly set up by An Post and Ordnance Survey Ireland, manages Ireland's only complete database of commercial and residential buildings.
The figures are recorded through a combination of the An Post network of 5,600 delivery staff working with OSI.
The 5,620 new buildings on the database consisted of 4,837 residential buildings, 590 commercial buildings and 913 dual-purpose buildings with both residential and commercial components.
Seven counties - Carlow, Clare, Cork, Galway, Leitrim, Offaly and Tipperary - saw an increase in new buildings for the first half of the year, according to GeoDirectory.
The highest increase was recorded in Cork, where 777 residential and 69 commercial properties were completed in the first six months of the year. But Kerry recorded the lowest number of new additions with just 30 residential and five commercial properties built in the six month period.
GeoDirectory also noted there was a vacancy rate of 12% for new building additions, which in effect means that nine out of ten new commercial and residential buildings are occupied.
Leitrim has the highest vacancy rate for new buildings at 20%, while it also saw the largest year on year increase of 323%.