What cavity wall insulation costs after the grant
Cavity wall insulation typically costs €2,350 for a detached house, €1,585 for a semi-detached or end of terrace, €1,250 for a mid-terrace and €1,036 for an apartment. After the SEAI grant about €550, €285, €400 and €336 are left to pay. On the higher rate, a semi-detached house's grant covers the typical cost.
The typical cost by house type, the grant off it, the BER on top, and the higher rate.
Free, no obligation. One registered installer prices it, not five.
- about €285left to pay on a semi-D, typically
- about €550on a detached house
- about €400on a mid-terrace
- about €230the post-works BER, after its €50 grant
All in, with the BER
Every grant claim needs a BER after the work. It typically costs €245 to €280, and SEAI pays €50 towards it.
| Home type | Insulation, after the grant | BER, after its grant | All in | All in, higher rate |
|---|---|---|---|---|
| Detached | about €550 | about €230 | about €780 | about €280 |
| Semi-D or end of terrace | about €285 | about €230 | about €515 | about €230 |
| Mid-terrace | about €400 | about €225 | about €625 | about €375 |
| Apartment | about €336 | about €195 | about €531 | about €331 |
Check your cavity wall grant
Four quick taps. You see your grant as you go, then what the job typically costs after it, the BER and your next step. Your number is only asked for at the end, if you want a price.
A semi-detached built before 2011, no earlier wall grant: a €1,300 grant, and the job typically costs €1,585, so about €285 is left to pay.
How this is worked out
SEAI pays a fixed cavity wall grant for each house type, and a higher fixed amount to homeowners on certain welfare payments and to landlords with a HAP or RAS tenant. The typical cost is the median price of cavity wall insulation for your house type across thousands of grant-funded jobs, and the post-works BER is its median price less its own grant. Your installer prices your walls after a look: it's a guide to plan with, never a quote. SEAI decides every grant.
What moves the price
- How much outside wall there is. A detached house has four outside walls, a mid-terrace two. That's why the price, and the grant, change with the house type.
- What's in the cavity now. Some cavities are empty and some are partly filled already. The installer looks before giving you a price.
- Getting at the walls. Extensions, conservatories, porches and high gables all have to be reached.
- Every wall, not some. The grant needs every outside wall insulated, so the price is for the whole house.
Paying the rest
On the usual route you pay the installer, then SEAI pays you the grant 4 to 6 weeks after it has your forms. Through a One Stop Shop the grant comes off your invoice instead. For a bigger upgrade, Home Energy Upgrade Loans run from €5,000 to €75,000, with rates from 2.99%.
The order matters: no work before approval.
Cavity Wall Insulation Grants guides & price breakdowns
Straight answers to what people ask most: itemised costs, specifications, planning or grants, and what to check before you book.
More guides & resources: The BER after cavity wall insulation · Had a wall grant before? The second wall measure · All guides & calculator hub · Technical & trade glossary · Frequently asked questions · All areas covered
Questions people ask
How much does cavity wall insulation cost in Ireland?
Typically €2,350 for a detached house, €1,585 for a semi-detached or end of terrace, €1,250 for a mid-terrace and €1,036 for an apartment, before the grant.
How much is cavity wall insulation after the grant?
Cavity wall insulation typically costs €2,350 for a detached house, €1,585 for a semi-detached or end of terrace, €1,250 for a mid-terrace and €1,036 for an apartment. After the SEAI grant about €550, €285, €400 and €336 are left to pay. On the higher rate, a semi-detached house's grant covers the typical cost.
Does the higher rate cover the whole cost?
For a typical semi-detached house, yes: €1,700 against a typical €1,585. For a detached house about €50 is left, a mid-terrace about €150.
Do I pay the full price first?
On the usual route, yes: you pay the installer and SEAI pays you after the claim. A One Stop Shop takes the grant off your invoice instead.
Is the BER extra?
Yes. It typically costs €245 to €280 and SEAI pays €50 towards it.
Cavity Wall Insulation Grants across all 26 counties
Requests from all 26 counties go to one vetted local specialist who covers your county — from Dublin, Cork, Galway and Limerick to Kildare, Meath, Wicklow, Waterford and Donegal. Pick your county below for local prices, specifications and advice. Compare all areas covered →
Check your cavity wall grant
Four taps to your grant and what's left to pay, then one SEAI-registered installer who covers your county rings with a price.