There were 4,920 new homes completed between April and June, according to the CSO, an 11.8% increase year-on-year.
More than half of those - 2,834 - were part of a scheme, which is classified as a development of two or more houses.
That figure is 2.6% higher than in the same three months of 2018.
Almost 760 apartments were built in the period, up 55.6% year-on-year. Meanwhile there was a 15.5% increase in single dwelling builds, which stood at 1,328 in the quarter.
The figures are based on ESB connections, which may also include older homes that are reconnected.
To counter this the CSO says it uses additional information from the ESB, as well as data from other sources.
It also notes that the figures currently do not cover the growing student accommodation sector, which is treated as a commercial rather than residential connection by the ESB.
The CSO said there were 329 'bed spaces' completed for students in the second quarter, with 6,691 completed since the same period of 2016.
Dublin accounted for 31% of all new dwellings
During the three month period 1,546 dwellings were completed in Dublin, with a further 1,233 completed in the mid-east. Together they accounted for more than half of all new dwellings.
Meanwhile Naas was the Eircode with the most new dwellings in the quarter, with 204 completions registered.
The CSO said the number of ghost estates - many of which were left unfinished after the financial crash - continued to fall, with the number of previously finished dwellings in unfinished housing developments down almost 22% year-on-year.
It said these types of units now made up only 2.4% of all ESB domestic connections, compared to 21.7% in 2014.
The CSO data also shows a 5.8% fall in the average size of new dwellings between the first half of 2018 and this year.