Housing completions were up by over a fifth in the first three months of 2019, according to Goodbody's Housebuilding Tracker.
It uses Building Energy Regulation (BER) data to compile its figures.
The official data tracks electricity connection figures.
According to Goodbody's figures, 4,255 residential units were completed in the first quarter, an increase of 22% over the same period last year.
It says under 2,500 of these were accounted for by housing schemes.
Apartment completions grew by almost two thirds in the first three months, the data shows.
"As we noted in our Q4 Tracker, planning permissions data was pointing to a large increase in apartment output, although the timing is quite uncertain. At 18% of the total, the proportion of output coming from apartments remains quite small," Goodbody chief economist Dermot O'Leary said.
Dublin and the surrounding counties accounted for over half of the total completions in the period.
Mr O'Leary said the figures for Q1 were in line with its forecasts of 22,000 housing completions for the full year.
Goodbody's figures pointed to housing supply reaching a nine year high in 2018, but still remains at half of the country's estimated demand.
It said 18,855 new dwellings were completed in Ireland last year.