Cavity Wall Insulation Grant Ireland — Up to €2,300 from SEAI
Cavity wall insulation is one of the most cost-effective home improvements available — low installation cost, meaningful energy savings, and an SEAI grant that covers a large portion of the bill. This guide covers who qualifies, grant amounts by property type, and how to apply correctly.
Check If My Home QualifiesGrant Amounts by Property Type
Two rate tiers apply: standard and enhanced (for homeowners on qualifying welfare payments).
| Property type | Standard rate | Enhanced (welfare) |
|---|---|---|
| Detached house | €1,800 | €2,300 |
| Semi-detached / End of terrace | €1,300 | €1,700 |
| Mid-terrace | €850 | €1,100 |
| Apartment | €700 | €900 |
Grant amounts from SEAI.ie, March 2026. Verify current rates at seai.ie before applying.
Who Qualifies?
Home built before 2011
The property must have been built and occupied before 31 December 2010.
Cavity walls must be present and suitable
Not all homes have suitable cavities — a survey by your installer confirms this before application. Stone or brick solid-wall homes are not eligible for this specific grant.
No prior cavity wall grant
If you or a previous owner has already claimed this grant for the property, you cannot claim again.
SEAI-registered contractor
Work must be carried out by a contractor registered with SEAI for cavity wall insulation.
Apply before work starts
Grant approval from SEAI must be obtained in writing before the contractor begins any work.
How to Apply
Get a cavity wall survey
Your installer checks whether the cavity is suitable — correct width, no major defects, no risk of damp penetration. This is usually free and done before you apply.
Get quotes from SEAI-registered contractors
Only SEAI-registered cavity wall contractors are eligible. Verify at seai.ie/contractor-register. Get at least 2–3 quotes.
Apply online at hes.seai.ie before work starts
Submit your application with your MPRN (on your ESB bill), property details, and contractor details. Wait for written approval.
Work is completed
Cavity fill typically takes half a day. The installer drills holes in the outer leaf, injects insulation (mineral wool or EPS bead), and makes good.
Grant paid
After the contractor submits completion paperwork to SEAI, the grant is processed.
Do not start work before receiving written approval from SEAI. Starting installation before approval permanently disqualifies you — no exceptions.
Typical Cost vs Grant
| Item | Typical range |
|---|---|
| Cavity wall insulation (semi-detached) | €800–€2,000 |
| SEAI grant (semi-detached, standard rate) | −€1,300 |
| Your net cost (indicative) | Often €0–€700 |
Costs vary by property size and contractor. Get multiple quotes. Some homeowners pay little or nothing after the grant.
Apply directly at SEAI.ie
All applications through the official SEAI portal.
Check All the Grants Your Home Qualifies For
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