Upgrade · Heat · the heating · BER file 26 Sep 2026 · checked 8 Sep 2026
77% of older A- and B-rated houses still heat with a boiler
A new boiler makes the same heat from less fuel. 77% of older houses rated A or B still heat with an oil, gas or LPG boiler (SEAI BER file, 26 Sep 2026): they got there with the fabric. A unit of heat from oil costs 18.0c, from a heat pump 9.82c. There's no grant for a new boiler.
A new wall-hung gas boiler in a kitchen being refitted. It burns less to make the same heat.
New Kitchen (6130290558) · marsupium photography · CC BY-SA 2.0
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See your grants for a heat pump, and what you’d pay
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77%
Older A- and B-rated houses on an oil, gas or LPG boiler
Houses built before 2011 · BER file 26 Sep 2026
BER assessment34.5%
Homes sold or let heated by oil
BER file 8 Sep 2026
BER assessment18.0c
A unit of heat from oil. From a heat pump: 9.82c
SEAI fuel cost comparison · 1 Jul 2026
Published figure€2,000
Boiler scrappage grant, only when a heat pump replaces it
SEAI heat pump systems · read 3 Oct 2026
SEAI ruleUpdated · grants checked · BER file · prices SEAI H1 2026 · How we know · Corrections
Where this sits · the heat chain
The heating only puts back what the house loses. A heat pump works best when the house loses less.
- Fabricwalls, roof, floor, windows
- Airdraughts and ventilation
- Heatheat pump or boiler, radiators, controls
- Usebills, comfort, the BER
- The idea behind itFabric first: the heat-loss line
- You are hereA new oil or gas boiler
- Next questionWhat's the boiler scrappage grant?
A heat pump's heat has cost less than oil or gas heat in all 31 SEAI editions since 2019
What a unit of heat has cost in each of SEAI's fuel cost editions: oil, gas and a heat pump. Published figure
A heat pump's heat has cost less than oil or gas heat in all 31 SEAI editions since 2019
In Jul 2026 a kWh of heat cost 9.82c from a heat pump, 14.45c from mains gas and 18.00c from oil. Oil spiked to 27.04c in Apr 2026, 2.8 times the heat pump.
Each step is one quarterly edition of SEAI's Domestic Fuel Cost Comparison, Jan 2019 to Jul 2026 (31 editions), turned into the cost of a kWh of heat delivered into the home: electricity on band DD divided by a seasonal performance factor of 3.5 for the heat pump, mains gas on band D2 at 90%, kerosene (schedule price, 1,000 litres) at 70%. Jul 2019: heat pump 5.89c, gas 7.62c, oil 12.06c. Jul 2022, at the height of the energy crisis: oil 22.13c. Oct 2022: gas 17.15c. Jul 2026: heat pump 9.82c, gas 14.45c, oil 18.00c. The Apr 2026 oil price, €1.93 a litre, is the highest in SEAI's series back to 1990. At a seasonal performance factor of 2.5 instead of 3.5, heat from a heat pump would have cost more than gas heat in 13 of the 31 editions, all before April 2022, and 13.75c in Jul 2026.
EstimateOne efficiency per fuel (heat pump 3.5, gas 90%, oil 70%), from SEAI's own table; a real home's will differ.
Sources: SEAI Domestic Fuel Cost Archive (xlsx, sheet 'Archive-D ckWh'), 5 Oct 2026 · SEAI Domestic Fuel Cost Comparison (efficiency table), 1 Jul 2026
The numbers
| Edition | Heat pump | Gas | Oil | Oil ÷ heat pump |
|---|---|---|---|---|
| Jan 2019 | 6.16c | 8.46c | 10.87c | 1.76 |
| Jul 2019 | 5.89c | 7.62c | 12.06c | 2.05 |
| Jan 2020 | 6.31c | 8.49c | 12.29c | 1.95 |
| Jul 2020 | 5.96c | 7.43c | 8.78c | 1.47 |
| Jan 2021 | 6.55c | 7.79c | 9.66c | 1.47 |
| Jul 2021 | 6.11c | 6.89c | 11.96c | 1.96 |
| Jan 2022 | 7.24c | 8.70c | 14.02c | 1.94 |
| Jul 2022 | 6.54c | 9.41c | 22.13c | 3.38 |
| Jan 2023 | 9.03c | 17.15c | 17.98c | 1.99 |
| Jul 2023 | 8.15c | 16.28c | 15.79c | 1.94 |
| Jan 2024 | 10.73c | 18.20c | 16.92c | 1.58 |
| Jul 2024 | 7.91c | 14.13c | 17.62c | 2.23 |
| Jan 2025 | 8.41c | 14.96c | 16.32c | 1.94 |
| Jul 2025 | 8.57c | 13.54c | 15.57c | 1.82 |
| Jan 2026 | 8.57c | 13.54c | 15.51c | 1.81 |
| Apr 2026 | 9.82c | 14.45c | 27.04c | 2.75 |
| Jul 2026 | 9.82c | 14.45c | 18.00c | 1.83 |
The heat pump grant covers up to 87% of a typical semi-D job
There's no grant for a new boiler. This is what SEAI pays when a heat pump replaces it. SEAI rule
The heat pump grant covers up to 87% of a typical semi-D job
Against SEAI’s median costs, grants cover up to 87% of a heat pump and 82% of cavity wall insulation, but 23% of heating controls and 19% of solar panels.
Each bar is the job's median cost for a semi-D (SEAI, January to June 2026); the filled part is the grant on the individual route. Heat pump: €10,500 for the unit, €2,000 for the heating system and, since 29 Sep 2026, a €2,000 boiler scrappage grant: €14,500 of €16,741, or 75% without the scrappage grant, which needs an oil, gas, solid-fuel or storage-heating system removed.
Sources: SEAI grant pages, transcribed in pipeline/inputs/grants_2026.csv, 3 Oct 2026 · SEAI, Median costs of individual energy upgrades, Jan-Jun 2026 (H1 2026), 2026
The numbers
| Job | Grant | SEAI median cost | Share |
|---|---|---|---|
| Heat pump | €14,500 | €16,741 | 87% |
| Cavity wall insulation | €1,300 | €1,585 | 82% |
| Attic insulation | €1,500 | €2,101 | 71% |
| Windows | €3,000 | €7,110 | 42% |
| Internal wall insulation | €3,500 | €9,843 | 36% |
| External wall insulation | €6,000 | €23,219 | 26% |
| Heating controls | €700 | €3,000 | 23% |
| Solar panels | €1,800 | €9,500 | 19% |
What a new oil or gas boiler actually changes
A new boiler makes the same heat from less fuel. It does nothing about the heat the house is losing, and there is no grant for one.
What a boiler does
A boiler burns fuel and hands the heat to the water going round your radiators. How much of the fuel actually reaches the water is the boiler's efficiency, and that is the only thing a new one changes.
The gap is real. SEAI's fuel comparison assumes a gas boiler at 90%, with condensing models running anywhere from 85 to 97%, and an oil boiler at 70%, with a range of 60 to 75%. An old oil boiler at the bottom of that range wastes nearly a third of every litre it burns. Replacing it is a genuine improvement.
It is also the end of the improvement. The new boiler heats the same rooms through the same walls under the same cold attic, and it burns the same fuel at the same price per litre.
What it fixes and what it leaves alone
| A new boiler | Insulation | Controls | A heat pump | |
|---|---|---|---|---|
| Heat the house loses | unchanged | less | unchanged | unchanged |
| Fuel burned per unit of heat | less | unchanged | unchanged | a different fuel entirely |
| Heat you make when nobody's home | unchanged | unchanged | far less | unchanged |
| Cost of a unit of heat | oil 18.0c, gas 14.4c | — | — | 9.8c |
| Grant | none | see the insulation pages | €700 | up to €10,500 for the unit, €1,000 to €2,000 for pipework and a €2,000 boiler scrappage grant for taking out the oil or gas boiler |
| Reliability | new kit, new warranty | nothing to break | nothing much to break | new kit, new warranty |
Assumed efficiencies, SEAI Domestic Fuel Cost Comparison, 2026-07-01 edition: gas boiler 90% (condensing 85–97%), oil boiler 70% (60–75%), stove 50% (50–80%). Useful c/kWh: gas 14.4c, oil 18.0c, bulk LPG 25.2c, heat pump 9.8c at SPF 3.5. No grant exists for a fossil-fuel boiler: S.I. No. 749 of 2024, in force 1 January 2025, transposing Article 17(15) of Directive (EU) 2024/1275.
Where the saving comes from — and where it stops
Think of the bill as two numbers multiplied: how much heat the house needs, and how dear each unit of that heat is. A boiler only touches the second one, and only by the size of the efficiency gap — worth having on a bad old boiler, worth little on a decent one.
Insulation attacks the first number, and it keeps working for forty years without being serviced. That is why the order of work on every other page here starts with the roof. If money is tight, the roof and the walls will do more for the same euro than a boiler swap will, and they leave the house ready for whatever heats it next.
When a new boiler is still the right call
A new oil or gas boiler is still allowed in an existing home; public grants for one ended in January 2025. Are oil and gas boilers being banned?
Three cases, honestly.
The boiler has died and the house is cold. Heat now beats a plan for March.
The house is nowhere near ready for a heat pump and won't be for years — solid walls, single glazing, no money for fabric work yet. A heat pump forced into that house runs badly and costs a fortune to run.
There's no realistic route to the electric option: no space for an outdoor unit, a flat where the plumbing isn't yours to change, a rented house you don't own.
In all three, take the controls grant while the system is open. It is the one piece of public money still on the table, and it is worth €700.
Questions people ask
- Is there a grant for a new gas or oil boiler?
- No. SEAI do not grant-aid a new or replacement fossil-fuel boiler, and it is not a rule they can bend for an emergency. Since 1 January 2025 Irish law forbids public bodies from putting money toward installing a stand-alone fossil-fuel boiler. You can still buy one and still fit one; the State just will not help pay for it.
- Are oil and gas boilers being banned?
- Not in existing homes, and no date has been set for one. The binding rule is the funding ban that started in January 2025. The often-quoted 2040 comes from a reporting template in an EU directive, where national plans have to describe a phase-out "with a view to" that year. New houses are a different story and it is already settled — building standards made fossil boilers impractical in new homes years ago.
- My boiler died in January. What should I do?
- Get it looked at before you replace it, because a repair can be grant-aided where a replacement cannot, and a failed part on a twelve-year-old boiler is often worth fixing. If it does have to go, take the heating controls grant at the same time — the system is already open and the work is already being done. Do not let a cold week decide the next twenty years of heating.
How we know
- Ratings: From SEAI's BER Research Tool (files of 8 Sep 2026 and 26 Sep 2026): certificates for homes sold or let, and every certificate for houses built before 2011. A BER is a standard calculation, not a meter reading.
- One job at a time: Our model reworks each certificate with one job done, on the BER file of 26 Sep 2026. Its heat loss matches SEAI's own figure to a median ratio of 1.00. A group figure, not an assessment of your house.
- Grants and prices: SEAI's grant pages, read on the dates shown, and SEAI's median costs of individual upgrades for 2025. A median is a middle price, not a quote.
Sources
seai.ie · support for individual grants · seai.ie · heating upgrade grants · seai.ie · Domestic Fuel Cost Comparison · oireachtas.ie · 768 · eur-lex.europa.eu · HTML
Found a mistake? Every fix is dated on Corrections. Method in full: How we know.
See your grants and what you’d pay
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Updated · grants checked · BER file · prices SEAI H1 2026 · How we know · Corrections