The highest rating category of A0 was received by 3,006 dwellings since it was introduced on 24 May 2026 (See Table A and Figure 1).
All dwellings with A0 ratings used electricity as the main space heating fuel due to the requirement of zero emissions from fossil fuels (See Table 6).
The most common main space heating fuel among BER rated dwellings was Mains Gas (34%), closely followed by Heating Oil (34%) and Electricity (26%) (See Table 9).
Over one-third (36%) of dwellings with a BER received an A0, A, or B rating in Q2 2026 (See Table A and Figure1).
Solar energy installations, either thermal or photovoltaic, were present in 16% of rated dwellings at the time of assessment (See Table 13).
On 24 May 2026, the Building Energy Rating (BER) scale was reduced from 15 categories to 8 (A0, A, B, C, D, E, F and G) for both domestic and non-domestic buildings. For this release, the now-deprecated subcategories of BER (A1, A2, A3, B1, B2, B3, C1, C2, C3, D1, D2, E1 and E2) have been assigned their parent rating (A, B, C, D, and E) and are presented together with the BERs awarded under the new system.
The A0 category is an entirely new category for buildings that are both energy-efficient and do not produce carbon dioxide emissions from fossil fuels.
Please see the Background Notes for more details on the changes to the rating system introduced on 24 May 2026.
Due to incompatibility between the different rating scales, data table EBA02 can no longer be maintained. It has been archived and replaced by table EBQ02. Users with feedback to offer on this change can contact CSO Climate and Energy through the details provided in the side menu.
The BER systems introduced A0 ratings for the first time on 24 May 2026. Buildings rated A0 are Zero Emission buildings, which are both energy efficient and produce zero carbon emissions from fossil fuels.
By the end of June 2026, over 3,000 dwellings had received the A0 rating since it was introduced on 24 May 2026 (See Table A).
| Table A: Total Number of BER'S by Energy Rating as of Quarter 2 2026 | |
| Energy Rating | Number of Dwellings |
| A0 | 3,006 |
| A | 252,834 |
| B | 239,659 |
| C | 419,257 |
| D | 224,158 |
| E | 106,424 |
| F-G | 122,267 |
| Total | 1,367,605 |
The number of domestic Building Energy Rating (BER) audits published in Q2 2026 was 51,162. In total, over 1.8 million BER audits have been published from 2009-2026 (See Table 1).
Over 99% of audited dwellings built since 2020 received a rating of A or A0. A or A0 ratings were received by 93% of dwellings built from 2015-2019, 39% of those built from 2010-2014 and 6% built between 2005-2009 (See Figure 2 and Table 2).
The highest rating category of A0 was received by 3,006 dwellings since 24 May 2026 (See Table A).
| A0 | A | B | C | D | E | F | G | |
| 1900-1977 | 0 | 4 | 10 | 21 | 22 | 17 | 10 | 17 |
| 1978-1999 | 0 | 4 | 17 | 41 | 27 | 8 | 2 | 1 |
| 2000-2004 | 0 | 3 | 23 | 54 | 15 | 4 | 1 | 0 |
| 2005-2009 | 0 | 6 | 43 | 43 | 7 | 2 | 0 | 0 |
| 2010-2014 | 0 | 39 | 53 | 6 | 1 | 0 | 0 | 0 |
| 2015-2019 | 0 | 93 | 6 | 0 | 0 | 0 | 0 | 0 |
| 2020-2024 | 0 | 99 | 1 | 0 | 0 | 0 | 0 | 0 |
| 2025-2029 | 7 | 93 | 0 | 0 | 0 | 0 | 0 | 0 |
The highest proportion of A/A0 rated dwellings were in Co. Kildare (30%), Co. Meath (28%) and Dublin County (29%). The lowest proportion of A/A0 rated dwellings were in Co. Leitrim (6%) and Cork City (6%).
The highest proportions of G rated dwellings were in Co. Roscommon (11%) and Co. Leitrim (11%).
In the Dublin Postal Districts, the highest proportion of A/A0 ratings were in Dublin 18 (45%), Dublin 13 (32%) and Dublin 20 (27%) (See Table 5).
All dwellings with A0 ratings used electricity as the main space heating fuel, due to the zero emissions from fossil fuels requirement (See Table 6).
The use of Mains Gas as the main space heating fuel was most common in Cork City (70%) and Dublin County (62%). Heating oil was most common in Donegal (72%), Mayo (68%) and Roscommon (67%) (See Table 8).
The most common main space heating fuel among BER-rated dwellings was Mains Gas (34%), closely followed by Heating Oil (34%) and Electricity (26%) (See Table 9).
Heating oil was the most common fuel type used for main space heating in detached houses (64% of those with a BER), and the least common type among apartments (6% of apartments with a BER) (See Table 10).
| Mains Gas | Heating Oil | Electricity | |
| 2000-2004 | 39 | 37 | 20 |
| 2005-2009 | 42 | 32 | 20 |
| 2010-2014 | 37 | 34 | 20 |
| 2015-2019 | 40 | 5 | 47 |
| 2020-2024 | 6 | 0 | 86 |
| 2025-2029 | 1 | 0 | 95 |
Detached houses were the most common dwelling type to have received a BER since 2009, contributing 33% of the overall rated stock by count. Among dwellings built since 2020, apartments were the highest proportion by dwelling type (37%) (See Table 11).
Energy from solar electric panels or solar thermal collectors was present in 16% of rated dwellings. This proportion was highest in detached houses (26%) and lowest in apartments (5%) (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 since 2020 (See Table 14).
Among those dwellings which have received more than one BER assessment, 232,158 saw an improvement of at least one full letter category over their initial energy rating. Of these, 370 were upgraded to an A0 rating (See Table 15).
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Statistician's Comment
The Central Statistics Office (CSO) has today (26 August 2026) published Domestic Building Energy Ratings (BER) for Quarter 2 (Q2) 2026.
Commenting on the release, Kevin Hunt, Statistician in the Climate and Energy Division, said: “In May 2026 a new BER rating system was introduced. The highest rating is now A0, which is for Zero Emission Buildings, which are both energy efficient and have no fossil fuel emissions. As of Q2 2026, more than 3,000 dwellings had received an A0 BER rating (See Table A and Figure 1).
Of the 1.37 million unique dwellings receiving a BER rating since 2009, 18% were rated A0 or A, 18% were rated B, and 31% were rated C (See Figure 1 and Table 2).
Main Space Heating Fuel
The most common main space heating fuel among BER rated dwellings was Mains Gas (34%), closely followed by Heating Oil (34%) and Electricity (26%) (See Table 9).
All dwellings with A0 ratings used electricity as the main space heating fuel, due to the zero emissions from fossil fuels requirement (See Table 6)
Proportion of Rated Dwellings with Renewable Energy
Energy from solar electric panels or solar thermal collectors was present in 16% of rated dwellings. This proportion was highest in detached houses (26%) and lowest in apartments (5%) (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 since 2020 (See Table 14).
Energy Ratings by Period of Construction
The highest rating category of A0 was received by 3,006 dwellings since 24 May 2026.
More than 99% of audited dwellings built since 2020 received a rating of A or A0. A or A0 ratings were received by 93% of dwellings built from 2015-2019, 39% of those built from 2010 to 2014 and 6% built between 2005 and 2009 (See Figure 2 and Table 2).
Local Area Analysis
The highest proportion of A or A0 rated dwellings were in Co. Kildare (30%), Co. Meath (28%) and Dublin County (29%). The lowest proportion of A or A0 rated dwellings were in Co. Leitrim (6%) and Cork City (6%). The highest proportions of G rated dwellings were in Co. Roscommon (11%) and Co. Leitrim (11%) (See Table 4).
In the Dublin Postal Districts, the highest proportion of A or A0 ratings were in Dublin 18 (45%), Dublin 13 (32%) and Dublin 20 (27%) (See Table 5).
Dwellings with Improved Energy Ratings
Among those dwellings which have received more than one BER assessment, 232,158 saw an improvement of at least one full letter category over their initial energy rating. Of these, 370 were upgraded to an A0 rating (See Table 15)”.