In designated rent-pressure zones, which cover Dublin and major commuter towns as well as Galway and Cork cities and part of Limerick, councils will need to grant planning approval for any short-term letting of investment properties.
The Department of Housing said in a recent letter to all local authorities that it was unlikely that any of these applications would be approved due to the housing shortages.
People renting out their main homes on a short-term basis will also be barred for doing so for more than 90 days each year without planning permission, while those offering stays under this threshold would have to register with their local authorities.
However all the onus for policing the regulations will also rest on the local authorities, which many say are ill-prepared to handle extra enforcement cases given the difficulties involved in investigating short-term lets and recession-era staff cuts.