Mains gas and heating oil were the most common main space heating fuel in rated dwellings (both 34%) (See Table 8).
Mains gas was the most common space heating fuel in the Dublin region (61% gas heated) and the Mid-East region (39% gas heated) in homes with a Building Energy Rating (BER) (See Table A and Figure 1).
Heating oil was most common among rated dwellings in the Border (67% oil heated) and West (60% oil heated) (See Table A and Figure 1).
Over one third (35%) of dwellings with a BER have received an A or B rating (See Table 2).
Solar energy installations, either thermal or photovoltaic, were present in 15% of rated dwellings at the time of rating (See Table 13).
Heat pumps were installed in over 80% of rated dwellings constructed since 2020, compared with 15% of all rated dwellings (See Table 14).
This release includes links to a new open data table EBQ02. Table EBQ02 contains a quarterly snapshot of all domestic BER assessments which were valid in a particular quarter. This data can therefore be used to create a historical time series of BER ratings from the current quarter back to Q4 2009. The number of BER certificates and the level of coverage has increased significantly in this time period.
Table EBQ02 also includes data on renewable energy installations. The actual number of renewable energy installations is likely to be higher than those counted in this release, as not all dwellings have received a BER assessment. There may also be cases where a renewable energy source was installed after a BER assessment was made.
Table EBA02 has more detailed BER assessment data, including year of publication and County or Dublin postal district. It only contains data which is valid in the current period. The number of BER ratings in EBA02 will therefore be equal to the most recent quarterly period in table EBQ02.
In the titles of the tables that follow, the years “2009-2026” describe the period when all BER certificates were published. Figures 2 and 3, and Tables 2, 9, 11, 12, and 14, also use years to refer to the period in which rated buildings were constructed, which can affect energy efficiency.
The Background Notes contains more details on coverage and definitions.
Across the State, the most common main space heating fuel in rated dwellings up to Q1 2026 was mains gas (34%), followed by heating oil (34%), and electricity (25%) (See Table A and Table 9).
There was regional variation for this distribution. Mains gas was the most common space heating fuel in Dublin (61% gas heated) and the Mid-East region (39% gas heated).
By comparison, heating oil was most common in all other regions: Border (67% oil heated), West (60% oil heated), Mid-West (48% oil heated), South-East (49% oil heated), South-West (37% oil heated) and Midland (49% oil heated).
Table 8 has a more detailed breakdown of main space heating fuel by county. These figures do not include dwellings without BER ratings.
The number of domestic Building Energy Rating (BER) audits published in Q1 2026 was 40,961. This was 9% higher than the equivalent number published in the same quarter of 2025. In total, almost 1.8 million BER audits have been published from 2009-2026 (See Table 1).
Newer builds were more energy efficient than older stock. A ratings were awarded to 100% (rounded) of all audited dwellings built in 2025-2029, 99% of those from 2020-2024, and 94% of those built between 2015-2019. In comparison, 38% of dwellings built between 2010-2014 and 6% of the dwellings built from 2005-2009 have received an A rating (See Figure 2 and Table 2).
| A | B | C | D | E | F-G | |
| 1700-1977 | 4 | 9 | 21 | 22 | 17 | 27 |
| 1978-1999 | 3 | 16 | 41 | 28 | 9 | 3 |
| 2000-2004 | 3 | 22 | 55 | 16 | 4 | 1 |
| 2005-2009 | 6 | 42 | 43 | 7 | 2 | 0 |
| 2010-2014 | 38 | 54 | 6 | 1 | 0 | 0 |
| 2015-2019 | 94 | 6 | 0 | 0 | 0 | 0 |
| 2020-2024 | 99 | 1 | 0 | 0 | 0 | 0 |
| 2025-2029 | 100 | 0 | 0 | 0 | 0 | 0 |
The highest proportions of A rated dwellings were in Kildare (30%), Meath (28%), and Dublin County (28%), while the lowest were in Leitrim (6%) and Cork City (6%). The highest proportions of G rated dwellings were in counties Roscommon (11%) and Leitrim (11%) (See Table 4).
In the Dublin postal districts, the highest proportions of A ratings were in Dublin 18 (44%), Dublin 13 (31%), and Dublin 20 (27%) (See Table 5).
The most common main space heating fuel in audited dwellings was mains gas (34%), followed by heating oil (34%), and electricity (25%) (See Table 9).
Mains gas for space heating was most common in Cork City (70%), Dublin County (62%), and the Dublin postcodes (61%). Heating oil was most common in Donegal (72%), Mayo (68%), and Roscommon (67%) (See Table 8).
A ratings were given to 53% of dwellings using electricity as the main space heating fuel, 8% of those using mains gas, and 2% of those using heating oil (See Table 6).
For dwellings built since 2015, electricity was the most common space heating fuel (See Figure 3 and Table 9).
| Mains Gas | Heating Oil | Electricity | |
| 2000-2004 | 39 | 37 | 20 |
| 2005-2009 | 42 | 32 | 20 |
| 2010-2014 | 38 | 34 | 20 |
| 2015-2019 | 40 | 5 | 47 |
| 2020-2024 | 6 | 0 | 86 |
| 2025-2029 | 1 | 0 | 95 |
The average floor area for all rated dwellings was 118 m2. The dwelling type with the largest average floor area was detached houses (168 m2) while the smallest type was basement apartments (63 m2) (See Table 12).
Energy from solar electric panels or solar thermal collectors was present in 15% of rated dwellings. This proportion was highest in detached houses (25%) and lowest in apartments (5%). By county, the highest proportion of dwellings with solar energy was 24% in Meath, 22% in Kildare and 21% in Dublin County (See Table 13).
A heat pump was present in 15% of rated dwellings where the main space heating fuel was identified (See Table 14). This proportion was highest in newer builds, with heat pumps present in 84% of dwellings built in 2020-2024 (See Table 14).
Among those dwellings which have received more than one BER assessment, 220,096 saw an improvement of at least one full letter category over their initial energy rating. Of these, 51% went from a C rating or below in their first rating to an A or B in their most recent assessment (See Table 15).
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Statistician's Comment
The Central Statistics Office (CSO) has today (01 May 2026) published Domestic Building Energy Ratings (BER) for Quarter 1 (Q1) 2026.
Commenting on the release, Kevin Hunt, Statistician in the Climate and Energy Division, said: “The number of new domestic BER assessments published in Q1 2026 was 40,961. This takes the total number of published audits from 2009-2026 to almost 1.8 million, which includes dwellings with multiple BERs (See Table 1).
Of the 1.35 million unique dwellings receiving a BER rating since 2009, 18% were rated A, 17% rated B, and 31% rated C (See Table 2).
Main Space Heating Fuel
Mains gas was the most common main space heating fuel in rated dwellings (34%) followed by heating oil (34%) and electricity (25%) (See Table 8).
A ratings were given to 53% of dwellings using electricity as the main space heating fuel, 8% of those using mains gas, and 2% of those using heating oil (See Table 6).
Proportion of Rated Dwellings with Renewable Energy
Solar energy installations, either thermal or photovoltaic, were present in 15% of rated dwellings at the time of rating (See Table 13). By type of dwelling, detached houses had the highest proportion of solar energy (25%) and apartments had the lowest (5%).
Heat pumps were installed in 15% of all rated dwellings where information on the main space heating source was available (See Table 14). The proportion was higher in newer builds, with heat pumps installed in over 80% of dwellings constructed since 2020.
Energy Ratings by Period of Construction
Newer builds were more energy efficient than older stock. A ratings were awarded to over 99% of audited dwellings built since 2020, and to 94% of those built between 2015-2019. In comparison, 38% of dwellings built between 2010-2014 and 6% of the dwellings built from 2005-2009 received an A rating (See Figure 2 and Table 2).
Local Area Analysis
The highest proportions of A rated dwellings were in Kildare (30%), Meath (28%) and Dublin County (28%), while the lowest were in Leitrim (6%) and Cork City (6%). The highest proportions of G rated dwellings were in counties Roscommon (11%) and Leitrim (11%) (See Table 4).
In the Dublin postal districts, the highest proportions of A ratings were in Dublin 18 (44%), Dublin 13 (31%) and Dublin 20 (27%) (See Table 5).
Mains gas for space heating was most common in Cork City (70%), Dublin County (62%), and the Dublin postcodes (61%). Heating oil was most common in Donegal (72%), Mayo (68%), and Roscommon (67%) (See Table 8).
Dwellings with Improved Energy Ratings
Among those dwellings which have received more than one BER assessment, over 220,000 saw an improvement of at least one full letter category over their initial energy rating. Of these, 51% went from a C rating or below in their first rating to an A or B in their most recent assessment (See Table 15)."