Grant pages tell you what you can claim. They rarely tell you what the job costs, which is the number you actually need. These pages do both. Every figure below comes either from SEAI's own completion data for the first half of 2026, or from a documented Irish household we can point you at. Where the honest answer is that prices vary wildly, we say so and give you the range anyway.
| Measure | Typical cost | Grant | You pay | Basis |
|---|---|---|---|---|
| Attic insulation | €1,515 to €2,700 | €1,100 to €2,000 | €415 to €800 | SEAI medians, Jan to Jun 2026 |
| Cavity wall insulation | €1,036 to €2,350 | €700 to €1,800 | €336 to €700 | SEAI medians, Jan to Jun 2026 |
| Internal wall insulation | €5,736 to €9,843 | €1,500 to €4,500 | €4,100 to €7,804 | SEAI medians, Jan to Jun 2026 |
| External wall insulation | €11,300 to €26,500 | €3,000 to €8,000 | €8,300 to €18,500 | SEAI medians, Jan to Jun 2026 |
| Air to water heat pump | €9,025 to €17,000 | €9,500 to €12,500 | €0 to €4,500 | SEAI medians, Jan to Jun 2026 |
| Solar PV | €9,075 to €11,100 | €1,800 capped | €7,275 to €9,300 | SEAI medians, Jan to Jun 2026 |
| Windows, whole house | €4,196 to €10,453 | €1,500 to €4,000 | €2,696 to €6,453 | SEAI medians, Jan to Jun 2026 |
| External doors | €3,176 to €4,300 | €800 per door, two max | €1,576 to €2,700 | SEAI medians, Jan to Jun 2026 |
| BER assessment | €245 to €280 | €50 after works | €195 to €230 | SEAI medians, Jan to Jun 2026 |
| Whole house, One Stop Shop | €20,638 to €66,304 | €10,300 to €25,975 | €10,338 to €40,835 | SEAI, 583 homes, Jan to Jun 2026 |
Low end of each range is an apartment, high end is a detached house. These are medians, which means half of all completed jobs cost more. They come from 23,412 individual upgrades and 583 One Stop Shop homes completed between January and June 2026 and submitted to SEAI by registered contractors at the point of grant payment.
A median is the middle of a pile. Half the jobs cost more than the figure beside it, and some cost a great deal more. On the One Stop Shop route SEAI publishes the spread as well as the middle, and the spread tells the real story: 38 per cent of homes completed in the first half of 2026 had works costing over €75,000, another 32 per cent landed between €50,000 and €75,000, 23 per cent were €30,000 to €50,000, and only 7 per cent came in under €30,000.
So seven jobs in ten cost more than €50,000 before grants. If someone has quoted you thirty for a whole house, work out what is not in it before you celebrate.
The other thing the medians hide is that your house is a specific shape. External wall insulation is priced by wall area, not floor area, so a small bungalow with a big perimeter costs more per square metre of living space than a two storey semi. Solar is priced by kWp, and small arrays have the worst unit economics because scaffolding, inverter and labour are close to fixed costs. Each of the pages below gives you the per unit figure so you can price your own house rather than borrowing somebody else's.
Every SEAI grant is a fixed euro amount set by measure and by dwelling type. A detached house gets €8,000 for external wall insulation whether the job costs €18,000 or €30,000. That is the single most misunderstood thing about the scheme, and it is why grant coverage looks so different from measure to measure.
On the 2026 medians, the cheap measures are heavily supported and the expensive ones are not. Cavity insulation on a detached house is €2,350 against an €1,800 grant, which is 77 per cent. Attic insulation is €2,700 against €2,000, which is 74 per cent. External wall insulation on the same house is €26,500 against €8,000, which is 30 per cent. Solar PV is €11,100 against a capped €1,800, which is 16 per cent.
Add up what you can claim across the measures you are considering on the grant calculator, then subtract it from your quote yourself rather than trusting the deduction on the invoice.
From 3 February 2026 the heat pump system grant became a fixed €12,500. That is €6,500 for the heat pump, €2,000 for radiators and pipework, and a new €4,000 renewable heating bonus for coming off fossil or solid fuel. It was €6,500 before, so this is the biggest single change to the scheme in years. Attic and cavity grants also rose.
From 2 March 2026 a windows and doors grant was introduced on the individual grant route, first time buyers got a higher attic insulation grant designed to cover most or all of the cost, people on qualifying welfare payments got higher attic and cavity grants, and homeowners who had already taken a cavity or internal wall grant became able to claim a second wall insulation measure.
This matters when you read older price threads. Almost every quote posted on Irish forums before 2026 was priced against the old table, so the net figures in them are worse than what you would get today. The gross costs in them have not fallen. Take the gross number and apply the current grants yourself.
The BER scale also changed on 24 May 2026. Bands are now A0, A, B, C, D, E, F and G, the old subdivisions are gone, and the One Stop Shop target is a B rather than a B2. Certificates issued before that date stay valid for ten years. More on that on our BER page.
A One Stop Shop gives you one contract, one point of contact and grants netted off your invoice. You pay for that. Project management fees of €7,000 and €8,000 turn up repeatedly in real quotes we collected, and SEAI itself grant aids a project management line worth up to €2,000 on a detached house.
Documented spreads between the two routes are large. One homeowner priced windows, 3.5 kW of solar, a gas boiler, attic and cavity at €50,000 net through a One Stop Shop, against €30,000 to €35,000 going contractor by contractor. Another was quoted €31,000 ex VAT for an external wrap that direct contractors were pricing verbally at €18,000.
The individual route is cheaper and much more work. You pick each contractor off the SEAI register, claim each grant yourself and sequence the measures in the right order. If you are chasing a heat pump you have to hit the heat loss threshold first, which usually means the fabric work has to come before the plant. See how the One Stop Shop route works and how the individual route works.
Medians tell you the middle. They do not tell you what it felt like. We compiled 61 documented Irish households with real euro figures, from newspapers, regional energy agencies and forum threads, and 47 of them carry both a grant figure and a total cost.
The headline finding is a €44,000 spread. One homeowner sent an identical technical assessment report to two SEAI registered One Stop Shops and got back €102,000 net and €58,000 net for the same 240 sq m dormer. Registration is an eligibility and quality gate. It is not a price control.
The full set, with the source beside every figure, is on what Irish homeowners actually paid. It is the page to read before you sign anything.
Tell us where you are and what you are considering. We will introduce providers covering your area, so you can hold three real prices against the figures on this page.
On SEAI's data for 583 One Stop Shop homes completed January to June 2026, the median works cost was €20,638 for an apartment, €52,099 for a mid terrace, €62,881 for a semi-detached and €66,304 for a detached house before grants. Thirty eight per cent of those jobs cost over €75,000.
Cavity wall insulation and attic insulation. On the 2026 medians the grant covers about 77 per cent of a detached cavity job and about 74 per cent of a detached attic job, leaving you a few hundred euro. External wall insulation and solar sit at the other end, at about 30 per cent and 16 per cent.
SEAI's published medians are the costs submitted by registered contractors at the point of grant payment, so they are the amounts invoiced. When you compare your own quotes, always check whether each one is ex VAT or inc VAT, because a 13.5 per cent difference on a €60,000 job is over €8,000.
Usually one of four reasons: your house is bigger or a harder shape than the median, the quote includes work that is not an energy upgrade such as rewiring or making good, it is a bundled One Stop Shop price with project management inside it, or it is simply expensive. Get two more quotes before assuming it is the first three.
To claim a grant, yes. If you decide to do the work without grants you can use whoever you like. Several homeowners in our evidence base chose that route deliberately, either because their trusted builder is not registered or because the prerequisites for the grant were more expensive than the grant itself.
The median cost across completed jobs in the first half of 2026 was €245 for an apartment up to €280 for a detached house. There is a €50 grant towards a post works BER. One itemised One Stop Shop quote carried a BER certificate at €650.88 with no grant against it, so ask what yours costs.
Checked against the official pages on 27 August 2026. Grant terms change, so confirm current amounts with SEAI or your installer before you commit.