A total of 162,799 Building Energy Rating (BER) certificates were awarded to new and existing dwellings in 2025. This was 6% more than in 2024, and the most of any year for the period 2009-2025 (See Table 1).
By the end of 2025, over one quarter (26%) of the 1.3 million dwellings with BER ratings had at least one source of renewable energy present, an increase in proportion compared with the same quarter of 2024 (23%) and 2023 (19%) (See Table A and Figure 1).
Solar energy, both thermal and electric, was present in 15% of BER rated dwellings by Q4 2025, or over 195,000 homes (See Figure 1, Table A and Table 13).
Heat pumps were installed in 14% of all BER rated dwellings, or over 180,000 homes. Newer builds were more likely to include heat pumps, including 85% of those built since 2020 (See Table 14).
A ratings were received by 99% of dwellings built from 2020-2025, compared with 18% of the total rated stock (See Figure 2 and Table 2).
Electricity was the main space heating fuel for 94% of all rated dwellings built from 2020-2025, compared with 26% of the total rated stock (See Figure 3 and Table 9).
Mains gas and heating oil were the most widely reported space heating fuels, at 35% of BER rated dwellings each. (See Figure 3 and Table 9).
A new open data table on changes in the numbers of dwellings with renewables by quarter is now available: EBQ01.
The category of solar energy used in this release includes both solar thermal installations for heating and solar photovoltaic installations for electricity generation.
The actual number of renewable energy installations will likely be higher than those counted in this release. Not all dwellings have received a BER assessment, and among those that have, a renewable energy source may have been installed after their most recent BER assessment.
Please refer to the Background Notes for more details on definitions and coverage.
Of the BER rated households where the main space heating fuel can be identified, 26%, or over 343,000, had at least one source of renewable energy present when considering heat pumps, solar thermal systems, and solar photovoltaic panels. This was 23% higher than the 278,000 audits reported at the end of 2024 (See Figure 1).
The number of domestic Building Energy Rating (BER) audits published in Q4 2025 was 42,996. A total of 162,799 Building Energy Rating (BER) certificates were awarded to new and existing dwellings in 2025. This was 6% more than in 2024, and the most of any year for the period 2009-2025. In total, 1.7 million BER audits have been published from 2009-2025 (See Table 1).
Newer builds were more energy efficient than older stock. A ratings were awarded to 99% of all audited dwellings built in 2020-2025, and 94% of those built between 2015-2019. In comparison, 38% of dwellings built between 2010-2014 and 5% of the dwellings built from 2005-2009 received an A rating (See Figure 2 and Table 2).
| A | B | C | D | E | F-G | |
| 1700-1977 | 3 | 9 | 21 | 22 | 17 | 27 |
| 1978-1999 | 3 | 15 | 41 | 28 | 9 | 3 |
| 2000-2004 | 3 | 21 | 55 | 16 | 4 | 1 |
| 2005-2009 | 5 | 42 | 44 | 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 (29%), Meath (28%) and Dublin County (28%), while the lowest were in Leitrim and Cork City (both 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 (28%) (See Table 5).
The most common main space heating fuel in audited dwellings was mains gas (35%), followed by heating oil (35%) and electricity (26%). For dwellings built since 2015, electricity was the most common space heating fuel. Dwellings constructed from 2020-2025 were 94% electrically heated (See Figure 3 and Table 9).
| Mains Gas | Heating Oil | Electricity | |
| 2000-2004 | 39 | 37 | 20 |
| 2005-2009 | 43 | 33 | 20 |
| 2010-2014 | 40 | 35 | 21 |
| 2015-2019 | 43 | 6 | 50 |
| 2020-2025 | 6 | 0 | 94 |
The average floor area for all rated dwellings was 117 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 (24%) and lowest in apartments (5%). By county, the highest proportion of dwellings with solar energy was 23% in Meath, 21% in Kildare and 21% in Dublin County (See Table 13).
A heat pump was present in 14% 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 85% of dwellings built in 2020-2025 (See Table 14).
Among those dwellings which have received more than one BER assessment, 210,112 saw an improvement of at least one full letter category over their initial energy rating. Of these, 50% 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 (22 January 2026) published Domestic Building Energy Ratings (BER) for Quarter 4 (Q4) 2025.
Commenting on the release, Kevin Hunt, Statistician in the Climate and Energy Division, said: “The number of domestic BER assessments reported in 2025 was 162,799, an increase of 6% over the total for 2024 (See Table 1).
Number of Dwellings with Building Energy Certificates
The total number of audits published from January 2009 to December 2025 was 1.7 million, including dwellings with multiple assessments (See Table 1).
Of the 1.3 million unique dwellings to receive a BER since 2009, 18% received an A rating in their most recent assessment (See Table 2).
Proportion of Rated Dwellings with Renewable Energy
Of the BER rated households where the main space heating fuel can be identified, 26%, or over 343,000, had at least one source of renewable energy present when considering heat pumps, solar thermal systems, and solar photovoltaic panels. This was 23% higher than the 278,000 audits reported at the end of 2024 (See Table A and Figure 1).
Energy from solar electric panels or solar thermal collectors was present in 15% of rated dwellings by Q4 2025. This proportion was highest in detached houses (24%) and lowest in apartments (5%) (See Table 13). By county, the highest proportion of dwellings with solar energy was 23% in Meath, 21% in Kildare and 21% in Dublin County (See Table 13).
A heat pump was present in 14% of rated dwellings where the main space heating fuel could be identified (See Table 14). This proportion was highest in newer builds, with heat pumps present in 85% of dwellings built from January 2020 to December 2025 (See Table 14).
Energy Ratings by Period of Construction
Newer builds were more energy efficient than older stock. A ratings were awarded to 99% of audited dwellings built from 2020-2025, and to 94% of those built between 2015-2019. In comparison, 38% of dwellings built between 2010-2014 and 5% of the dwellings built from 2005-2009 received an A rating (See Figure 2 and Table 2).
Main Space Heating Fuel
The most common main space heating fuel in audited dwellings was mains gas (35%), followed by heating oil (35%) and electricity (26%). For dwellings built since 2015, electricity was the most common space heating fuel. Dwellings constructed from 2020-2025 were 94% electrically heated (See Figure 3 and Table 9).
Dwellings with Improved Energy Ratings
Among those dwellings which have received more than one BER assessment, 210,112 saw an improvement of at least one full letter category over their initial energy rating. Of these, 50% went from a C rating or below in their first rating to an A or B in their most recent assessment (See Table 15).
Energy Ratings by County and Dublin Postal District
The highest proportions of A rated dwellings were in Kildare (29%), Meath (28%) and Dublin County (28%), while the lowest were in Leitrim and Cork City (both 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 (28%) (See Table 5)."