Fewer than 18,000 homes are expected to be completed this year, according to a report from Goodbody Stockbrokers.
Prior to the onset of the coronavirus, around 35,000 new homes a year were needed to meet demand.
In the first three months of 2020 growth in home-building activity slowed to the lowest rate since the end of 2013.
As construction sites were only forced to close at the end of March, this suggests the slowdown in house completions had already started before the Covid-19 crisis reached Ireland.
In the three months to 31 March this year new dwelling completions grew by 6pc year-on-year to 4,500 units.
Given the current shutdown, coupled with expected social distancing measures when sites reopen and the changed economic environment, it is expected there will be a “significant” fall in output for the rest of the year, according to the report.
Dermot O’Leary, analyst at Goodbody, said: “Growth in home completions in Ireland were slowing even before lockdown measures were introduced in late March, according to our latest BER Tracker for Q1 2020.”
“With the changed backdrop, completions are now likely to fall sharply in 2020, but the sector will be a key focus for policymakers in any recovery plan over the coming months,” he added.
House completions in the Greater Dublin Area fell by 4pc year-on-year in the first three months of 2020, with completions outside the GDA increasing by 21pc.
Growth in house completions was led in the West of the country, up 63pc, the Midlands – which saw an increase in completions of 56pc – and the Mid-West, which was up 18pc year-on-year, although these are all from much lower bases.
Elsewhere, apartment completions grew by 39pc year-on-year to circa 800.
Once attention turns to how to safely reopen the economy, it is likely the government will want construction, and housebuilding in particular, to be among the first industries to reopen, according to Mr O'Leary.
"However, the demand environment will be impacted negatively, and is likely to result in a reassessment of supply plans by some developers," he said.