RGI-registered engineers · Ireland
Boiler Installation in Ireland: Cost, Types and Registered Engineers
New combi, system, oil or heat-only boiler, with county-by-county guidance on what it costs, which type suits your home, what happens on the day, and how to choose an RGI-registered engineer for the job.
The short version
Boiler installation in Ireland costs €2,200 to €4,500 fitted in 2026, depending on the boiler type and your home. By law, any gas boiler must be installed by an RGI-registered engineer, and the register covers all 26 counties. Choose your county below for local prices and engineers, or read on for the boiler types, the 2026 costs, and what happens on installation day.
Whether you are swapping a tired combi in a Dublin terrace, moving an old back boiler onto a modern system, or replacing an oil boiler in rural Mayo, the same three things decide the job: the boiler type your home is plumbed for, whether you are staying like-for-like or changing system, and who you hire. Get those right and a new boiler is a clean one or two-day job with a warranty behind it.
Peace of mind
A Boiler Install You Can Trust
A new boiler is a big spend, so it should come with the paperwork to match. A registered installer, a Declaration of Conformance, and a warranty backed by an annual service are what separate a proper install from a cheap one.
Get those and the boiler is a one or two-day job you can forget about for years, not a saving that costs you later.
- A registered installer and completion cert
- A manufacturer warranty registered on the day
- An annual service to keep it valid
When to replace
Signs You Need a New Boiler in Ireland
A boiler rarely fails overnight. If yours is over twelve years old, needs repairs every winter, or costs more to run each year, a new boiler is usually cheaper long-term than another repair. These are the signs Irish plumbers see most.
Over 12 Years Old
Most boilers last twelve to fifteen years. Past that, parts get harder to source and efficiency falls away.
Rising Heating Bills
An older non-condensing boiler can run at 70 per cent efficiency or less, so you pay more for the same heat.
Frequent Repairs
Two or more call-outs in a winter usually means the next repair is money better spent on a new boiler.
Banging or Kettling Noise
Rumbling, banging or whistling points to sludge or scale, and often a boiler near the end of its life.
Cold Spots and Slow Heat
Radiators slow to warm, or hot at the top and cold at the bottom, point to a struggling system.
Lockouts or a Yellow Flame
Repeated lockouts, a boiler that keeps cutting out, or a yellow flame should be checked by an RGI engineer straight away.
The law
Boiler Replacement in Ireland: What the Law Requires
A boiler running on natural gas or LPG, whether a straight combi swap in a Dublin terrace or a replacement in a rural bungalow, must be installed by an RGI-registered gas installer. That is a legal requirement under the Energy (Miscellaneous Provisions) Act 2006, and an unregistered person cannot issue the Declaration of Conformance that certifies the work.
Oil boilers are different. Oil work sits outside the gas registration scheme, so look instead for an installer holding OFTEC oil-firing certification. Ask any installer to confirm which fuel they are certified for before you book, because gas and oil competence are not interchangeable.
- RGI registration is required by law for all gas boiler work
- An unregistered installer cannot issue the Declaration of Conformance
- Oil boilers need OFTEC certification, not RGI
- Confirm which fuel your installer is certified for before booking
How Long Does Boiler Installation Take?
A like-for-like combi swap takes one working day. Switching boiler type takes two days, while heat pumps take two to three.
SEAI Grants for Heating Upgrades
Up to €12,500 for a heat pump and €1,200 for solar water heating, through SEAI-registered contractors.
Oil Boilers Need OFTEC
Oil work sits outside the gas scheme, so for an oil boiler look for an OFTEC-certified installer rather than RGI.
You Get a Completion Cert
Every gas boiler install ends with a Declaration of Conformance, your legal proof a registered installer did the work.
The options
Which Boiler Type Is Right for Your Home?
Combi, system, regular heat-only or oil: each suits a different home and carries a different installed price. Here is what sets them apart before you get a quote.
Combi Boiler
Heats water on demand straight from the mains, with no cylinder or attic tank. The most popular choice in Irish homes built from the 1990s on, suited to houses and apartments under about 130 square metres with one or two bathrooms.
from€2,200
System Boiler
Works with a hot water cylinder but no cold tank in the attic, feeding pressure straight from the mains. Suits larger homes with several bathrooms and higher hot water demand, and pairs well with solar water heating.
from€2,800
Regular Heat-Only Boiler
Needs both a hot water cylinder and a cold water feed tank in the attic. Most common in older homes built before the 1980s, where a like-for-like swap keeps the existing pipework layout intact.
from€2,200
Oil Boiler
For homes off the gas network, common across rural Munster, Connacht and the border counties. Modern condensing oil boilers run at over 90% efficiency, and SEAI grants apply when you switch to a heat pump or solar thermal system.
from€3,000
2026 prices
How Much Does Boiler Installation Cost in Ireland?
Boiler installation in Ireland costs €2,200 to €4,500 fitted in 2026 for a like-for-like replacement, with labour and VAT included. A straightforward combi swap sits at the low end, while a regular-to-combi conversion or a new oil boiler sits at the top.
- Get three written quotes, each naming the boiler model
- A power flush on an older system adds €200 to €400
- Switching boiler type can add €600 to €1,200 in pipework
Every home is different. Your installer will price the job on the boiler, the pipework and your county, so treat the figures on the right as a budgeting guide, not a quote.
- Combi boiler, supply and fit €2,200–3,200
- System boiler, with cylinder €2,800–4,000
- Regular heat-only boiler €2,200–3,200
- Oil boiler, supply and fit €3,000–4,500
- Fit only, you supply the boiler €600–900
- Annual boiler service €80–120
Indicative ranges only. Always confirm with a written quote.
What Affects the Price of a New Boiler
Flue Relocation
Moving the flue outlet to a new spot on an external wall adds labour and materials to what would otherwise be a straightforward job.
Switching Boiler Type
Going from a regular boiler to a combi means removing the attic tank and cylinder and rerouting pipework, which can add €600 to €1,200.
System Flush
A power flush before fitting clears the sludge that shortens a new boiler’s life. Budget €200 to €400, especially on an older system.
Your County
Dublin and the commuter belt typically carry a 10 to 15 per cent premium over rural counties, down to demand and travel time.
SEAI grants
SEAI Grants for Boiler and Heating Upgrades in 2026
Grants are available for heat pump installation (up to €12,500) and solar water heating (€1,200). Standard gas combi replacements do not qualify directly, and the work must be carried out by an SEAI-registered contractor before any grant is claimed. If you are on oil and mains gas has reached your area, it is worth asking for a quote that includes any oil-to-gas conversion support.
See SEAI-registered plumbersOn the day
What to Expect on Boiler Installation Day
A like-for-like combi replacement is a single-day job. Here is how an RGI-registered engineer works through it, from isolating the supply to handing you the paperwork.
Isolate the Gas and Water
The installer shuts off and isolates the gas and water supply before the old unit is touched, so the work starts safe.
Remove the Old Boiler
The old boiler comes off the wall, and any redundant tank, cylinder or pipework is dealt with where the system is changing type.
Fit and Connect the New Unit
The new boiler is mounted and connected, the flue fitted or reused, and the pipework adjusted to suit the new unit.
Commission and Flue Gas Analysis
The installer fires the boiler, balances the system and runs a flue gas analysis to confirm safe, clean combustion.
Certificate of Completion
Your RGI installer hands you a Certificate of Completion. Do not make the final payment without it, as it is your legal record that a registered installer did the work.
Register the Warranty
The boiler warranty is registered with the manufacturer. Most then depend on an annual service to stay valid, so keep the service record with it.
Hiring
How to Choose a Boiler Installer in Ireland
Every gas boiler installer in Ireland must hold RGI registration by law, so start there. Beyond the legal minimum, a good quote is specific and a good installer is easy to check.
Check RGI Registration
Confirm the installer is on the public Register of Gas Installers of Ireland. Every engineer listed here is checked against it, and you can verify any number at rgi.ie.
Get Three Written Quotes
Each quote should name the exact boiler model, the labour, the flue materials and any pipework changes. A quote with no named boiler is incomplete.
Confirm SEAI Registration
RGI and SEAI are separate registers. If you are claiming a grant, your installer must be on both before any grant-funded work begins.
Get the Completion Certificate
Do not make the final payment until you have the Certificate of Completion. It is your legal proof a registered installer did the work, and you need it when you sell.
Local coverage
Boiler Installation by County in Ireland
What you pay, whether your home runs on gas or oil, and how fast an engineer can reach you all come down to where you live. Choose your county for local 2026 prices and RGI-registered installers.
Leinster
12 countiesMost of Leinster is on the natural gas grid, so gas combi and system boilers are the common choice, from Dublin terraces swapping out back boilers to new builds across the Meath, Kildare and Wicklow commuter belt.
Munster
6 countiesCork and Limerick cities sit on the gas network, but much of rural Munster, Kerry and west Cork included, is off-grid on oil or LPG. Oil boiler replacements and oil-to-heat-pump upgrades make up much of the work.
Connacht
5 countiesNatural gas barely reaches the west, so Galway, Mayo and the surrounding counties rely on oil, LPG and solid fuel. Exposed Atlantic weather and older rural homes mean steady demand for efficient boiler replacements.
Common questions
Boiler Installation Questions From Irish Homeowners
How much does combi boiler installation cost in Ireland in 2026?
A combi boiler supply and fit costs €2,200 to €3,200 in 2026 for a like-for-like replacement. Switching from a back boiler or regular system adds €600 to €1,200 for the pipework changes. These figures include labour and VAT.
How much does a new boiler cost in Ireland in 2026?
A combi runs €2,200 to €3,200 fitted, a system boiler €2,800 to €4,000 with a cylinder, a regular heat-only replacement €2,200 to €3,200, and an oil boiler €3,000 to €4,500. Brand, county and pipework changes move the final price.
Do I need an RGI engineer for boiler installation in Ireland?
Yes. All gas boiler installation in Ireland requires an RGI-registered engineer by law. An unregistered installer cannot certify the work, your home insurance may be invalidated, and the installation may not count towards a BER certificate.
What is the difference between a combi, system and regular boiler?
A combi heats water on demand with no cylinder or attic tank. A system boiler stores hot water in a cylinder but needs no attic tank. A regular, or heat-only, boiler needs both a cylinder and a cold water tank in the attic, and is typical in older Irish homes.
How long does boiler installation take in Ireland?
A like-for-like combi boiler replacement takes one working day. Switching boiler type takes two days. Heat pump installations take two to three days and may need extra work on your radiators and heating system.
Can I get an SEAI grant for a new boiler in Ireland in 2026?
SEAI grants are available for heat pump installation (up to €12,500) and solar water heating (€1,200). Standard gas combi replacements do not qualify for a direct SEAI grant, but insulation upgrades carried out at the same time may qualify separately.
Do I need a power flush when fitting a new boiler?
Most installers recommend a power flush or chemical clean before fitting, especially on an older system. Sludge in old radiators shortens a new boiler’s life and can void the warranty, so budget €200 to €400 for it.
How much does an annual boiler service cost in Ireland?
Annual boiler service costs €80 to €120 in Ireland in 2026. Servicing every 12 months is required by most manufacturers to keep the warranty valid and ensures the boiler meets gas safety requirements.
Find a Registered Boiler Installer Near You
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