THE owners of rundown empty houses will have to prove they are not fit to live in, to avoid paying the property tax on them.
There are thousands of houses in the countryside that have been left empty for years after the death of a family member. But they are still liable for the property tax because they have not yet fallen into a state of complete dereliction.
Now there are fears that the properties will be left to rot as owners avoid upkeep that would mean them paying the new tax.
In the past, householders opted to remove the roofs from old properties to avoid paying domestic rates on them.
The country's main auctioneering organisation warned that people should avoid making "rash decisions" to deliberately make their house uninhabitable.
There are 168,000 empty houses across the country – not including holiday homes, vacant apartments, derelict houses or houses under construction.
Even an old house that is barely fit to live in will attract a property tax bill of €90 a year. That is the lowest possible rate for houses valued at under €100,000.
The Revenue has confirmed that every house which is "suitable for use" is liable for the property tax, even if it is not being lived in.
It said owners will have to provide "appropriate documentary evidence" that the house is not fit to live in if they want to avoid the property tax. They will have to show that their empty house does not have basic necessities, which might include a roof, toilets, a water supply or an electricity supply.
Many householders may be tempted not to inform the Revenue about their ownership of an empty house. But there is a fine of up to €3,000 for providing an "incomplete or incorrect" property tax declaration to the Revenue by the May 28 deadline. The tax is due for payment from July 1 onwards.
If a homeowner wants to prove a house is uninhabitable, they can send photos of the property or a report from a quantity surveyor or engineer to the Revenue.
A decision will then be made on whether the house is liable for property tax.
"Each case will be considered on its own particular circumstances," said a spokeswoman for the Revenue.
But the Society of Chartered Surveyors warned householders against taking the roofs off run-down houses to ensure they escaped the property tax.
Its residential group chairman Ed Carey said that keeping the house in good condition could help a person get planning permission on the site in the future.
"If he takes the roof off it, then it becomes uninhabitable and he might diminish any possibility of getting planning on it in the future. Don't make any rash decisions," he said.
Mr Carey said the owners of extremely rundown empty houses should be able to prove they were not fit to live in by sending in photographs to the Revenue. He said that hiring a surveyor to produce an expert report should only be necessary where the condition of the house was a "grey area".
"Revenue is producing guidelines for homeowners. My suggestion is to wait and see what comes out from the Revenue and don't rush to any judgments."
About 55pc of the country's 168,000 vacant houses are in rural areas, with the remainder in cities.