Architects say it's not possible to design apartments according to new minimum sizes.
Last month the government relaxed rules for developers around the dimensions of new flats.
But the Royal Institute of the Architects says the while the overall size was reduced, the rules for rooms weren't.
It means kitchens and living rooms wouldn't be able to fit into smaller apartments.
RIAI Vice President John O'Mahony has told the Irish Times he doesn't think "anyone road tested this, because we have done a lot of research on this. It is not possible to design an apartment to the minimum sizes set down in the national standards."
