New research reveals counties where homes are cold, energy-inefficient and hard to heatLeitrim, Sligo and Tipperary top the rankings with the least energy-efficient homes in Ireland(Image: Getty)

Leitrim has been named Ireland’s coldest county to live in, according to new research.

The research, created by BioLPG experts Calor Gas, analysed average winter temperatures alongside the proportion of energy-inefficient homes across the country.

Using a new Cold Homes Index, counties were ranked based on how difficult it is to keep homes warm, factoring in both outside temperatures and how well homes retain heat.

Leitrim topped the national rankings, scoring 200 on the Cold Homes Index, the highest in Ireland. The county has one of the lowest average temperatures in the country and one of the highest concentrations of homes in BER bands D to G, which are considered the least energy efficient.

Sligo and Tipperary ranked second and third respectively, also recording large numbers of homes with poor insulation and outdated heating systems. Residents in these areas face a double blow of cold winters and heat-loss-prone housing, leading to higher bills and colder homes.

The top 10 counties with the coldest, least energy-efficient homes in Ireland are:

  • Leitrim – 200
  • Sligo – 192.35
  • Tipperary – 190.44
  • Mayo – 176.38
  • Longford – 171.85
  • Donegal – 171.33
  • Kerry – 168.75
  • Offaly – 163.84
  • Roscommon – 158.59
  • Westmeath – 156.87

Some people feel the cold more than others. (Image: Getty Images/iStockphoto)

Many of these counties are in the west and midlands of Ireland, where homes tend to be older, more rural and exposed to colder weather patterns – all of which contribute to heat loss and energy inefficiency.

At the other end of the scale, some counties are faring much better. Cork, Carlow and Waterford have some of the most energy-efficient homes, with a smaller proportion of homes in the D-G bands and slightly warmer average temperatures during the winter months.

The counties with the best performance on the Cold Homes Index include:

  • Cork – 51.28
  • Carlow – 71.59
  • Waterford – 72.33
  • Dublin – 77.00
  • Galway – 84.91

Oliver Kenny, Chief Commercial Officer at Calor Gas, commented on the findings, saying: “This data shows that where you live in Ireland can make a huge difference to how warm and comfortable your home feels and how much you’re spending on heating.

“At Calor, we’re committed to helping households, especially in rural areas, access more efficient heating solutions like BioLPG.

“Whether it’s through modern gas systems, renewable-ready setups or offering new connections and a free boiler to ensure they’re energy efficient, we want to ensure no one is left out in the cold.

“While insulation and smart upgrades are important, the energy we choose to heat our homes also matters. Cleaner, renewable-ready options like Calor BioLPG give households the chance to cut costs, improve comfort, and lower their carbon footprint, without compromising on warmth.”

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