Grant · Internal wall insulation · Semi-detached house · SEAI rules read 10 Oct 2026
Internal wall insulation grant for a semi-detached house: €3,500, leaving about €6,300 to pay
SEAI pays €3,500 for internal wall insulation (dry lining) on a semi-detached or end-of-terrace house (SEAI, read 10 October 2026). SEAI’s median price for the job on semi-detached houses in January to June 2026 was €9,843. That leaves about €6,300 to pay. The grant has to be approved before any work starts.
Insulation boards on a wall, mid-job. Dry lining puts them on the inside face of the outside walls.
Garrick Close, Kingston upon Hull: bungalow renovations, November 2023 · Hullian111 · CC BY-SA 4.0
See your grants for wall insulation, and what you’d pay
About 10 seconds. See your numbers first, then get quotes if you want them.
€3,500
SEAI's grant for a semi-detached house
SEAI grant page · read 10 Oct 2026
SEAI rule€9,843
SEAI's median price for the job
SEAI median costs · H1 2026 · Semi-detached or end of terrace
Published figure€6,343
Left to pay at SEAI's median price
€9,843 − €3,500
Published figure26%
Of semi-detached houses have solid or hollow-block walls, which cannot take cavity fill
SEAI BER file 8 Sep 2026 · existing homes since 2019 · n=80,466
BER assessment4–6 weeks
From complete paperwork to payment
SEAI grant pages · read 8 Sep 2026
SEAI ruleUpdated · grants checked · BER file · prices SEAI H1 2026 · How we know · Corrections
Where this sits · the grant steps
Every SEAI grant runs the same six steps. SEAI won't pay for work that starts before it approves.
- Assessa BER, or a home energy assessment
- Applyonline, before any work starts
- ApproveSEAI's offer lasts 8 months
- Worksby an SEAI-registered contractor
- Claimpost-works BER and forms
- Paid4–6 weeks after complete paperwork
- The idea behind itApply, approve, works and payment are different steps
- You are hereInternal wall insulation, semi-detached house
- Next questionHow do you apply, step by step?
What the grant pays on a semi-detached house
SEAI's median price for the job on semi-detached houses, January to June 2026, and every grant line on the individual route. SEAI rule
Grants pay €3,500 of a €9,843 job on a semi-detached house
SEAI’s grants take €3,500 off a €9,843 job, leaving about €6,300.
The left column is SEAI's median price for internal wall insulation (dry lining) on semi-detached houses, January to June 2026: what registered contractors charged on grant-aided jobs. The middle column is each grant on the individual route: Internal wall insulation (dry lining) €3,500. The right column is what is left at that price; a real quote will differ.
Sources: SEAI, Median costs of individual energy upgrades (H1 2026), 10 Oct 2026 · SEAI, Wall insulation grant, 10 Oct 2026
The numbers
| Job | Median cost | Grant |
|---|---|---|
| Internal wall insulation | €9,843 | €3,500 |
| Total | €9,843 | €3,500 |
The internal wall insulation grant for: detachedmid-terraceapartment
SEAI's rules for this grant, in its own words
Our plain version first, then SEAI's sentence as we read it. SEAI decides each application, not us. SEAI rule
Every external wall has to be insulated. SEAI rule
“To receive the grant, all external walls of your home must be fully insulated.”
SEAI, Wall insulation grant, read 10 Oct 2026
Cavity and internal insulation need no planning permission. SEAI rule
“Planning permission is not required for internal or cavity insulation.”
SEAI, Wall insulation grant, read 10 Oct 2026
Older solid stone or brick houses get no wall grant self-managed. SEAI rule
“SEAI Better Energy Homes Programme does not provide grant funding for wall insulation works on traditional buildings.”
SEAI, Individual grants: Homeowner Application Guide, read 10 Oct 2026
After a cavity wall grant, internal or external insulation can follow. SEAI rule
“If you previously received a grant for cavity wall insulation, you can apply for an internal wall insulation grant or an external wall insulation grant.”
SEAI, Wall insulation grant, read 10 Oct 2026
Approval takes minutes. Payment takes 4–6 weeks
Apply and get SEAI's offer before anything starts or is bought; then the works, a new BER, the claim and the payment. SEAI rule
Approval takes minutes and payment 4–6 weeks; the wait in between isn't published
SEAI publishes minutes from online application to offer, 30 days to accept, 8 months to finish and claim, and 4–6 weeks to pay. It publishes nothing for the assess, works or claim steps.
The six steps of the do-it-yourself grant route, in order. Under each step is the timing SEAI publishes, or a dashed box where it publishes none; we read every SEAI page, the terms and the homeowner guides on 8 Sep 2026. The 8-month window runs from the offer to the claim (One Stop Shop route: 12 months). Nothing starts before the offer. Work or materials paid for before it lose the grant. The marked step is the one this page is about: apply.
Sources: SEAI individual grant pages, as summarised in content/application-status.md, 8 Sep 2026 · SEAI How to apply and homeowner application guide, summarised in content/how-to-apply.md, 8 Sep 2026
The numbers
| Step | Who | Published timing |
|---|---|---|
| Assess | you + assessor | not published |
| Apply | you | minutes (online; by post ~5 working days) |
| Approve | SEAI | 30 days (to accept the offer) |
| Works | contractor | not published |
| Claim | you + assessor | not published |
| Paid | SEAI | 4–6 weeks (after complete paperwork) |
26% of semi-detached houses have solid or hollow-block walls, which cannot take cavity fill
Published BERs for semi-detached houses, by when they were built. A pattern across similar homes, not a fact about yours. BER assessment
81% of semi-detached houses built before 1940 have solid or hollow-block walls, which cannot take cavity fill
For semi-detached houses built 2005–2010 it is 4%. Across all ages it is 26%.
Each bar is the share of existing semi-detached houses with a BER since 2019, built in that era, whose certificate shows they have solid or hollow-block walls, which cannot take cavity fill. Before 1940: 81% of 8,747; 1940–1969: 44% of 13,061; 1970–1989: 24% of 16,301; 1990–2004: 12% of 27,490; 2005–2010: 4% of 14,867. A BER is a standard calculation, not a meter reading.
Sources: SEAI BER Research Tool (CC BY 4.0), 8 Sep 2026
The numbers
| Built | BERs | Share |
|---|---|---|
| Before 1940 | 8,747 | 81% |
| 1940–1969 | 13,061 | 44% |
| 1970–1989 | 16,301 | 24% |
| 1990–2004 | 27,490 | 12% |
| 2005–2010 | 14,867 | 4% |
Worked plans for semi-detached houses, by age: before 19401940 – 19691970 – 19891990 – 20062007 – 2010
Questions people ask
- Can I get a wall insulation grant for an old stone house?
- Not on the individual grants. SEAI does not fund wall insulation on traditional buildings, typically solid stone or brick built before 1940, through Better Energy Homes. Through a One Stop Shop they can get grants.
- Can I get a second wall insulation grant?
- After a cavity wall grant you can apply for internal or external wall insulation. After an external wall insulation grant you cannot get a second wall measure.
How we know
- Grants: SEAI's grant pages, read 10 October 2026. Every figure is the engine's, quoted from SEAI and re-checked against the export on every build.
- Prices: SEAI's median costs of individual upgrades for semi-detached houses, January to June 2026: what other homes paid, not a quote.
- Homes like this: SEAI's BER file of 8 September 2026, existing homes assessed since 2019. A BER is a standard calculation, not a meter reading.
Sources
SEAI, Wall insulation grant, 10 Oct 2026 · SEAI, Median costs of individual energy upgrades, 10 Oct 2026
Found a mistake? Every fix is dated on Corrections. Method in full: How we know.
See your grants and what you’d pay
Four questions about your home, then your numbers. Get quotes from registered contractors if you want them.
Updated · grants checked · BER file · prices SEAI H1 2026 · How we know · Corrections