There needs to be serious infrastructure changes if the Government plans to ban gas and oil boilers.
That's according to heating contractor John Corr, managing director of JCPS Mechanical.
Such a ban would apply to newly-built houses from next year, and to replacement installations in existing homes as soon as 2025.
The idea could see more district heating systems to replace the fossil fuel boilers.
That means taking heat generated by industry sources that is then pumped out to heat nearby homes.
Mr Corr said this could be a problem for places like Dublin city.
"At the moment I am aware that Dublin city's underground, the congestion of pipework, it's not possible to bring the pipelines up areas - or down through the city centre - to go out to a new estate that maybe is going to be built in South Dublin County Council".
Niall Farrell from the ESRI said it works in theory, but not for everywhere.
"If you're out in a rural area, like a lot of disbursed dwellings in Ireland, heat pumps would work.
"District heating is not so suited".
A report from the Office of Public Works (OPW), examining the ban for public buildings, has said several different technologies have the potential to play a role in replacing the boilers.
This includes low-temperature heat pumps and biomass boilers.
However it said there is is no one-size-fits-all solution.
"Different technologies have different advantages and disadvantages that influence their suitability for deployment in different building types", the April 2022 report said.
On district heating options, the report said this is "a well-proven technology that faces several barriers to deployment in Ireland.
"The anticipated significant growth in data centres in Ireland may present niche opportunities for heatpump-based district heating networks at appropriate locations.
"At least one public body is also investigating the feasibility switching an existing district heating system from fossil fuel (gas) with a deep-geothermal heat source.
"The phasing out of fossil fuels from existing buildings is a significantly more challenging proposition than that for new buildings.
"This is because the most promising alternative technologies are not drop-in replacements for existing fossil boilers and, in many cases, can only be deployed as part of large-scale building retrofit projects", it added.
Additional reporting: Andrew Lowth
