Two of Ireland's largest home builders are asking the High Court for permission to take judicial review proceedings over the new Wicklow County Development Plan.
Cairn Homes and Glenveagh Properties say the plan is based on outdated census data from six years ago, rather than the census conducted this year.
The result, the two companies claim, is that the number of homes which can be built under the plan has been significantly lowered.
The ceiling has been set at 8,467, which is 45% less than the 15,471 new homes previously targeted under the last plan.
Cairn and Glenveagh believe that the plan will force the council to refuse planning permission or restrict phasing on land that is serviced and zoned and previously deemed suitable for housing.
This will have a negative impact on the construction of social and affordable housing, it is claimed.
"It makes no sense to significantly reduce the capacity for building new homes throughout Wicklow, while our population is increasing and the societal need for new home delivery across all tenures has never been greater following a decade of undersupply," said Cairn’s chief executive, Michael Stanley.
"This is not good for Ireland and not good for Wicklow."
The plan is due to run from this year until 2028.
Since the last census, the population of county Wicklow has increased 9.2%.
"Our aim is to ensure that the Plan which is put in place for the coming years is ambitious and based on current data rather than historic data that gravely underestimates how many people will be living in Wicklow and how many homes are needed," said Glenveagh CEO, Stephen Garvey.
Wicklow County Council said it had no comment to make on the matter.
