Almost everyone budgeting an attic conversion assumes an SEAI grant will take a bite out of it. The internet is not much help here: half of what is written says a grant is only for the attic you are about to destroy, and the other half implies the money is waiting for you. Neither is right.
This guide is built on SEAI's own technical standards rather than on what contractors say about them. It answers one question: whether a grant is a line you can honestly put in your conversion budget.
The short answer
It is not a no, and it is not a yes. The measure itself is not disqualified: SEAI funds roof insulation at rafter level - the level a conversion insulates at - and its technical standards deal explicitly with a partial attic conversion. What decides your answer is which scheme you are asking, which part of the roof the work covers, and whether the person doing the work is registered with SEAI and pricing to SEAI's specification.
That last condition is the one that quietly ends it for most conversions. A grant is a retrofit instrument. It pays a registered contractor to install a defined measure to a defined standard. It is not a subsidy on a building job, and the builder quoting for your conversion has no particular reason to be inside that system.
Why there is not a single euro figure on this page
SEAI publishes fixed grant amounts by dwelling type, and sets eligibility conditions - including dwelling age - separately for each scheme. Both move. We would rather send you to the current values than print a number here that is quietly wrong a year from now, so every amount and every eligibility condition on this page is a link rather than a figure. What does not move is the answer to "which measure are you actually claiming for", and that is what the rest of this page is about.
SEAI states that the eligibility requirements for dwellings and for contractors are published per scheme on its website. Check the current amounts and conditions on seai.ie.
Ceiling level or rafter level: the distinction the whole answer turns on
These are two different measures, not two ways of saying insulation. SEAI treats them in two separate sections of its standards, with two different targets and two different sets of installation rules.
Ceiling level
Insulation laid across the floor of the attic, between and over the joists. The attic above it stays cold. This is the classic "attic insulation" job, and it is the cheap one.
Rafter level
Insulation in the slope of the roof itself, so the space underneath comes inside the heated part of the house. This is what a conversion does, because you cannot heat a room whose ceiling is the only insulated surface below it.
The reason this matters is that a conversion does not remove the grant-eligible measure. It changes which measure applies, and SEAI writes about the conversion case directly. Its standards say, of rafter level insulation:
"Where rafter level insulation is used on a partial attic conversion, the vertical walls of the room should have insulation placed between the stud timbers (where not already existing) and across the face of the stud walls. Where there is unused attic space outside of the conversion, insulation should be applied at ceiling level to the standard detailed in Clause 6.4 Insulation : Roof Insulation - Ceiling Level."
Source: SEAI, Domestic Technical Standards and Specifications v4.0, July 2026, clause 6.5(u). Read the document - read 10 September 2026.
Read that carefully, because it settles two things at once. Both measures can be live on the same roof: rafter level over the converted room, and ceiling level over whatever attic space is left outside it. And the knee walls - the short vertical walls at the edges of a converted attic, which builders often leave hollow - are treated as part of the roof upgrade, not as an optional extra.
Which scheme you are asking changes the answer
"An SEAI grant" is not one thing. There are three routes a homeowner realistically meets, they work differently, and they do not give the same answer to the same house.
You apply, you choose an SEAI-registered contractor, you manage the project, you pay the full cost of the works, and you claim the grant afterwards. SEAI states that the measures supported "include roof insulation at ceiling and rafter level".
This is the route that answers the question on this page, and the one the rest of it assumes.
Source: SEAI, Domestic Technical Standards and Specifications v4.0, July 2026, clause 1.1 - read 10 September 2026.
What we cannot tell you, and why we are saying so
SEAI's summary of what Warmer Homes covers is prefaced with "generally include", and it is preceded by the line about a technical surveyor deciding. An indicative list that names ceiling level is not a statement that rafter level is excluded, and we will not turn one into the other. If you are on that scheme and planning a conversion, the surveyor is the answer and asking SEAI directly is the only way to get it.
The conditions that decide it in practice
Assume for a moment that the measure is eligible and the scheme is the right one. Three conditions still stand between you and the money, and they are where most conversions come unstuck.
Under Better Energy Homes you select your preferred SEAI-registered contractor, and SEAI states that contractor registration is a mandatory requirement to carry out grant-funded works on some of its programmes. Registration is a separate process, aimed at retrofit contractors. A builder pricing an attic conversion has no particular reason to have been through it.
Ask early. If the answer is no, the grant is not in your budget, and finding that out after the plasterboard is up is the expensive version of finding out.
The two numbers below are the targets the insulation has to meet to be grant-funded. They are the most concrete thing on this page, and they are worth putting in front of a contractor.
0.16 W/m²K
Target maximum U-value, ceiling level (DTSS clause 6.4)
0.20 W/m²K
Target maximum U-value, rafter level, cold roof (DTSS clause 6.5)
Source: SEAI, Domestic Technical Standards and Specifications v4.0, July 2026, clauses 6.4 and 6.5, and corroborated in SEAI's Homeowner's Guide To Attic and Rafter Insulation - both read 10 September 2026.
Note what these are and are not. They are the standard a grant-funded measure has to reach. They are SEAI's numbers. Do not let anyone present them to you as the Building Regulations - see below.
Which material gets you there is a separate decision, and one we answer properly elsewhere: whatever you use has to achieve the U-value and be installed to the specification, so read our comparison of spray foam and rigid board before you let the material be chosen for you.
If the conversion is a few years away
This is the sequencing question, and it is the practical payoff of everything above. If you are thinking about taking a ceiling-level insulation grant now and converting later, clause 6.5(u) already told you where each measure ends up.
A conversion moves the insulated line from the ceiling up into the roof slope, over the footprint of the new room. Insulation laid at ceiling level under that footprint is not where the insulation ends up after the conversion. Over the attic space you leave unconverted, it is exactly where it should be, and SEAI says so.
One thing we are not going to claim
You will read elsewhere that taking the grant now means you can never claim again for the same roof. We looked for that rule in SEAI's technical standards and it is not in them. If it exists it lives in scheme terms and conditions we have not been able to read, so we are not going to state it as fact. Ask SEAI before you let it decide anything.
None of this makes the decision for you, and it is not financial advice. It puts the one thing you need in front of you: where each measure physically goes, and what the conversion does to that.
A grant standard is not Building Regulations compliance
This is the trap that follows the ceiling-versus-rafter one, and it is the same shape as the confusion between planning permission and Building Regulations. Two separate systems, doing different jobs, and clearing one does not clear the other.
SEAI's standards list the Building Regulations in twelve Parts, A to M - Part L being Conservation of Fuel and Energy - and state that the contractor "must adhere to the current version of the Building Regulations, at all times". That is an obligation SEAI places on a contractor doing grant work. It is not the instrument that decides which Parts apply to your conversion, and we are not going to pretend it is.
Source: SEAI, Domestic Technical Standards and Specifications v4.0, July 2026, clause 2.1 - read 10 September 2026.
Which Parts of the Building Regulations bind an attic conversion, and why, is a separate question with a separate answer - we set it out in our planning permission guide, which also separates planning exemption from Building Regulations compliance. The practical version for this page: a measure that meets SEAI's grant target has met SEAI's grant target. Whether your conversion complies with the Building Regulations is a different question, answered by different documents, and it is the one that matters when you come to sell the house.
Finding a registered contractor
Grant-funded work has to be done by a contractor registered with SEAI for the relevant scheme, and SEAI maintains that register. It is the only list that decides anything here.
We do not rank or recommend contractors
Not on this page and not anywhere on this site. We are not a directory, we take no payment to feature anyone, and naming a builder here would make our numbers worth less than they are. Go to SEAI's register and work from that.
One honest caveat about the link: SEAI's own homeowner guide prints a contractor-search address that no longer resolves at all - we checked it on 10 September 2026 and the host does not exist. So we point at seai.ie and let you find the current register from there, rather than send you to a dead page.
Separately from the grant question, vetting a builder is its own skill and we have a guide to it. Being on SEAI's register says a contractor is registered for retrofit work. It does not say they are the right person to convert your attic.
What we would do
Three situations, three different answers. Find yours.
You are converting now
Budget as though there is no grant, and treat one as a bonus if it lands. Ask two questions early: is the contractor registered with SEAI for the scheme, and will the rafter-level work be installed to SEAI's specification and hit the U-value target. If either answer is no, the grant is not available on this job, however eligible the measure is in principle. Knowing that at quote stage is worth more than the grant.
You are converting in a few years
Take the decision with clause 6.5(u) in front of you. Ceiling-level insulation grant-funded now sits at ceiling level; over the footprint you later convert, that is not where the insulated line ends up, and over the part you leave as cold attic it is. Ask SEAI directly what a later rafter-level application would look like before you decide - we could not read a rule on that in either direction, and neither should you accept one from a contractor.
You are not converting
Then this page is not really your question, and the answer is much simpler. Ceiling-level insulation is a well-defined SEAI measure with a published target and a register of contractors who install it. Go and take it.
What we would not do is let a grant decide whether the conversion happens. On the numbers a Dublin conversion actually costs - which we set out in our cost guide - an insulation grant is a rounding error against the job. It is worth having. It is not worth designing the build around, and it is certainly not worth choosing a contractor for.
Working out what your conversion will actually cost?
Our free planning tool covers insulation, ensuite decisions and everything else for your specific setup. It takes 2 minutes and you get a PDF you can take to your builder.
Try the Planning Tool