| Upgrade | Apartment | Mid-terrace | Semi-D / end | Detached |
|---|---|---|---|---|
| Cavity wall insulation | €700 | €850 | €1,300 | €1,800 |
| Internal wall (dry lining) | €1,500 | €2,000 | €3,500 | €4,500 |
| External wall insulation | €3,000 | €3,500 | €6,000 | €8,000 |
Standard 2026 SEAI rates, by dwelling type. Amounts are for guidance — confirm current figures with SEAI or your installer.
Cavity wall insulation is the cheapest and only works if your walls have a cavity to fill. Internal (dry lining) insulates from the inside and suits solid walls or single rooms. External wall insulation wraps the outside of the house and delivers the biggest improvement — and the biggest grant. Your installer or a BER assessor will advise which your home can take.
Your home must have been built and occupied before 2011 and the work carried out by an SEAI-registered contractor, with a BER assessment afterwards. You generally can't claim two different grants for insulating the same wall.
Tell us your county and we'll introduce SEAI-registered installers who cover your area.
Cavity wall ranges €700–€1,800, internal dry lining €1,500–€4,500, and external wall insulation €3,000–€8,000, depending on your dwelling type. Welfare recipients qualify for higher cavity rates.
Cavity wall insulation gives the best cost-per-euro if your home has fillable cavities. External wall insulation delivers the largest energy saving but costs the most, even after the grant.
Yes, and it's often required — your home usually needs to reach a good insulation standard before a heat pump grant is approved.