SEAI grant check · all 26 counties
Cavity Wall Insulation Grants and Prices
SEAI pays a fixed €700 to €1,800 by home type. A semi-D gets €1,300, against SEAI's own median cost of €1,585 for the first half of 2026. That leaves about €285 to pay.
FreeYour exact SEAI grant in 4 tapsOne SEAI-registered contractor rings you
Figures checked against seai.ie on 29 October 2026. How we check
Check your cavity wall grant
Four taps. Your grant first, then a price if you want one.
Step 1 of 4
What type of home is it?
Was it built and occupied before 31 December 2010?
SEAI only funds wall insulation in homes built and occupied before that date.
Has the home had an SEAI wall insulation grant before?
SEAI allows one more wall measure after a first wall grant, but not a second cavity fill.
Your SEAI grant
€1,800
Cavity wall insulation, detached house
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
A fixed amount, paid after the work. €2,300 if you get a qualifying welfare payment, or the home is in an active HAP tenancy or RAS arrangement.
SEAI's median cost for a detached house was €2,350 in the first half of 2026, so about €550 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your SEAI grant
€1,800
Cavity wall insulation, detached house
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI checks past grants against the home's MPRN. If the walls had a grant before, a second cavity grant isn't available.
SEAI's median cost for a detached house was €2,350 in the first half of 2026, so about €550 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your second wall measure
€4,500 or €8,000
Internal or external insulation, detached house
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI doesn't fund a second cavity fill. As a second wall measure it funds internal insulation (€4,500) or external insulation (€8,000).
The contractor can tell you which suits your walls. The grant is approved before any work starts.
From seai.ie, checked 29 October 2026.
Your second wall measure
€8,000
External insulation, detached house
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After internal insulation, SEAI's second wall measure is external insulation only. A cavity fill isn't funded.
The grant is approved before any work starts, and paid after.
From seai.ie, checked 29 October 2026.
Your SEAI grant
€1,300
Cavity wall insulation, semi-D
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
A fixed amount, paid after the work. €1,700 if you get a qualifying welfare payment, or the home is in an active HAP tenancy or RAS arrangement.
SEAI's median cost for a semi-D or end of terrace was €1,585 in the first half of 2026, so about €285 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your SEAI grant
€1,300
Cavity wall insulation, semi-D
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI checks past grants against the home's MPRN. If the walls had a grant before, a second cavity grant isn't available.
SEAI's median cost for a semi-D or end of terrace was €1,585 in the first half of 2026, so about €285 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your second wall measure
€3,500 or €6,000
Internal or external insulation, semi-D
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI doesn't fund a second cavity fill. As a second wall measure it funds internal insulation (€3,500) or external insulation (€6,000).
The contractor can tell you which suits your walls. The grant is approved before any work starts.
From seai.ie, checked 29 October 2026.
Your second wall measure
€6,000
External insulation, semi-D
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After internal insulation, SEAI's second wall measure is external insulation only. A cavity fill isn't funded.
The grant is approved before any work starts, and paid after.
From seai.ie, checked 29 October 2026.
Your SEAI grant
€1,300
Cavity wall insulation, end of terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
A fixed amount, paid after the work. €1,700 if you get a qualifying welfare payment, or the home is in an active HAP tenancy or RAS arrangement.
SEAI's median cost for a semi-D or end of terrace was €1,585 in the first half of 2026, so about €285 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your SEAI grant
€1,300
Cavity wall insulation, end of terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI checks past grants against the home's MPRN. If the walls had a grant before, a second cavity grant isn't available.
SEAI's median cost for a semi-D or end of terrace was €1,585 in the first half of 2026, so about €285 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your second wall measure
€3,500 or €6,000
Internal or external insulation, end of terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI doesn't fund a second cavity fill. As a second wall measure it funds internal insulation (€3,500) or external insulation (€6,000).
The contractor can tell you which suits your walls. The grant is approved before any work starts.
From seai.ie, checked 29 October 2026.
Your second wall measure
€6,000
External insulation, end of terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After internal insulation, SEAI's second wall measure is external insulation only. A cavity fill isn't funded.
The grant is approved before any work starts, and paid after.
From seai.ie, checked 29 October 2026.
Your SEAI grant
€850
Cavity wall insulation, mid-terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
A fixed amount, paid after the work. €1,100 if you get a qualifying welfare payment, or the home is in an active HAP tenancy or RAS arrangement.
SEAI's median cost for a mid-terrace was €1,250 in the first half of 2026, so about €400 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your SEAI grant
€850
Cavity wall insulation, mid-terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI checks past grants against the home's MPRN. If the walls had a grant before, a second cavity grant isn't available.
SEAI's median cost for a mid-terrace was €1,250 in the first half of 2026, so about €400 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your second wall measure
€2,000 or €3,500
Internal or external insulation, mid-terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI doesn't fund a second cavity fill. As a second wall measure it funds internal insulation (€2,000) or external insulation (€3,500).
The contractor can tell you which suits your walls. The grant is approved before any work starts.
From seai.ie, checked 29 October 2026.
Your second wall measure
€3,500
External insulation, mid-terrace
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After internal insulation, SEAI's second wall measure is external insulation only. A cavity fill isn't funded.
The grant is approved before any work starts, and paid after.
From seai.ie, checked 29 October 2026.
Your SEAI grant
€700
Cavity wall insulation, apartment
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
A fixed amount, paid after the work. €900 if you get a qualifying welfare payment, or the home is in an active HAP tenancy or RAS arrangement.
SEAI's median cost for an apartment was €1,036 in the first half of 2026, so about €336 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your SEAI grant
€700
Cavity wall insulation, apartment
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI checks past grants against the home's MPRN. If the walls had a grant before, a second cavity grant isn't available.
SEAI's median cost for an apartment was €1,036 in the first half of 2026, so about €336 is left to pay.
Grant from seai.ie, checked 29 October 2026. Cost: SEAI median, January to June 2026.
Your second wall measure
€1,500 or €3,000
Internal or external insulation, apartment
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI doesn't fund a second cavity fill. As a second wall measure it funds internal insulation (€1,500) or external insulation (€3,000).
The contractor can tell you which suits your walls. The grant is approved before any work starts.
From seai.ie, checked 29 October 2026.
Your second wall measure
€3,000
External insulation, apartment
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After internal insulation, SEAI's second wall measure is external insulation only. A cavity fill isn't funded.
The grant is approved before any work starts, and paid after.
From seai.ie, checked 29 October 2026.
SEAI wall grant
No second measure
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
After external insulation, SEAI doesn't fund another wall measure.
You can still get a price for work on the walls from one contractor who covers your area.
SEAI wall grant
Not eligible
cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
SEAI's wall insulation grant is only for homes built and occupied before 31 December 2010.
You can still get a price. One contractor who covers your area rings you about the walls and the work.
Sent. One contractor will ring you.
Keep your phone close and answer numbers you don't recognise for the next few days. Have your MPRN to hand: it's on your electricity bill.
Add more detail (optional)
It helps the contractor price the job before they ring. Tap what you know and skip the rest.
Rather talk now? Call 087 162 1846 (8am–8pm)
SEAI cavity wall grant, up to
€1,800for a detached house. Fixed by home type, the same in every county.
Higher rates for qualifying welfare recipients and homes in an active HAP tenancy or RAS arrangement: up to €2,300.
- Detached€1,800
- Semi-D or end of terrace€1,300
- Mid-terrace€850
- Apartment€700
From seai.ie, checked 29 October 2026.
After you send
What happens after you send your number
Four steps, in this order. Nothing is booked, and nothing is paid, until you say yes.
- 01
One contractor rings you
We pass your request to one SEAI-registered contractor who covers your area. Your number doesn't go to a list.
- 02
They survey the walls
A check of every wall, usually with a camera look into the cavity through a small drilled hole.
- 03
A written quote, grant set against it
A price with VAT stated. The SEAI grant is a fixed amount for your home type, so you see what's left to pay.
- 04
You decide
Nothing is booked until you say yes. If you go ahead, SEAI approves the grant before any work starts.
We don't do the work ourselves, and we are not SEAI. For the grant, the contractor must be on SEAI's register. You can check any contractor on the register before you agree to anything.
The figures
Cavity wall insulation in six numbers
Each one is linked to where it comes from.
- €1,300SEAI grant for a semi-D or end of terrace. €1,800 detached, €850 mid-terrace, €700 apartment.seai.ie, checked 29 October 2026
- €1,585SEAI's median cost for a semi-D or end of terrace, January to June 2026, from 23,412 completed upgrades.SEAI median costs PDF, read 29 Oct 2026
- €285Typical cost left to pay on a semi-D: the median cost less the grant.Our sum of the two figures above
- 1 dayHow long a house usually takes, according to a Dublin insulation company.Osber, page updated 31 Aug 2026
- €200–€400Yearly heating saving for a semi-D. saveonheat.ie's estimate from SEAI data, not a promise.saveonheat.ie
- 0.27The U-value, in W/m²K, the insulated wall must reach for the grant.SEAI guide
Before you agree
What a proper cavity wall job includes
Use this list when the contractor rings. Each line is something you can ask to see in the quote.
- A survey of every wall, with the cavity checked through a small drilled hole
- Air vents sleeved and flues checked, so the house keeps the air it needs
- Bonded bead, or another certified fill, pumped in from the bottom of the wall up
- The drilled holes filled to match the wall
- The paperwork SEAI needs for the grant
- A written price with VAT stated
Prices
What it typically costs after the grant
SEAI's own median cost for January to June 2026, less the current grant. Your quote can be higher or lower.
Compare grants
Three wall grants. Which one fits your walls
Cavity fill suits a cavity wall with an empty cavity. Solid walls take internal or external insulation, which get bigger grants because they are bigger jobs. Semi-D figures shown.
Guides
Cavity wall insulation guides
FAQ
Questions people ask
How much is the SEAI cavity wall grant?
SEAI pays €1,800 for a detached house, €1,300 for a semi-D or end of terrace, €850 for a mid-terrace and €700 for an apartment (seai.ie, checked 29 October 2026). Homeowners on a qualifying welfare payment, and homes in an active HAP tenancy or RAS arrangement, get €2,300, €1,700, €1,100 and €900.
What does cavity wall insulation cost after the grant?
SEAI's median cost for cavity wall insulation from January to June 2026 was €1,585 for a semi-D or end of terrace and €2,350 for a detached house (SEAI's own figures, from 23,412 completed upgrades). After the grant, that's about €285 for a semi-D and €550 for a detached house.
Who qualifies?
Homes built and occupied before 31 December 2010, with an MPRN. You must use an SEAI-registered contractor, get a grant offer before work starts, and fully insulate all external walls.
How long does it take?
Usually one day for a house. The contractor drills a pattern of small holes in the outer wall, pumps the insulation in and fills the holes to match.
Who will ring me?
We pass your request to one SEAI-registered contractor who covers your area. For the grant, the contractor must be on SEAI's register. They ring you, check the walls and give you a price. Nothing is booked until you say yes.
Is this site SEAI?
No. cavitywallinsulation.ie is not SEAI or a government body and does not award grants.
Sources (2)
Prices and facts on this page were checked against these published pages. We are not connected to these businesses.
- Osber: osber.ie
- saveonheat.ie: saveonheat.ie
See your grant, then get a price
Four taps show the SEAI grant for your home. Or call 087 162 1846 between 8am and 8pm and we pass you to one SEAI-registered contractor who covers your area.