Kilkenny · checked 29 October 2026

Cavity wall insulation in Kilkenny

The grant is national. The walls in Kilkenny aren't. What SEAI's BER register and Census 2022 say about homes in Kilkenny, Callan and Thomastown, and what it means for filling the cavity.

Figures checked against seai.ie on 29 October 2026.

cavitywallinsulation.ie is not SEAI or a government body and does not award grants.

33%of Kilkenny pre-2011 BERs: an empty or part-insulated cavity

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  • €1,800 detached, €850 mid-terrace, €700 apartment
  • About €285 left to pay on a semi-D
  • One SEAI-registered contractor rings you
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On Kilkenny's BER certificates for homes built before 2011, 3.7% record an empty cavity wall, the job this grant pays for, and 29% a cavity that's only part insulated, against 4.5% and 28% across Ireland. 13% are timber frame, which can't be cavity insulated, against 6% nationally.

The grant itself is the same in every county: €700 to €1,800 by home type, or €900 to €2,300 at the higher rate (seai.ie, checked 29 October 2026). We pass your request to one SEAI-registered contractor who covers Kilkenny.

What stands out about Kilkenny homes

SEAI pays the same grant in every county. The walls aren't the same. Against the national figures, these are the things that stand out in Kilkenny, from Kilkenny, Callan and Thomastown to the rest of the county:

  • 3.7% of Kilkenny's pre-2011 BERs record an empty cavity wall, against 4.5% nationally, the 19th highest of the 26 counties. That's a cavity wall with no insulation in it, U-value 1.0 or worse: the job this grant was made for.
  • 13% of Kilkenny's pre-2011 BERs are timber frame, against 6% nationally, the 3rd highest of the 26 counties. Timber frame homes can't be cavity insulated under SEAI's standards: the cavity keeps the frame dry (SEAI technical standards).
  • Detached houses are 59% of Kilkenny homes, against 41% nationally (Census 2022). They get the top cavity grant, €1,800, and have the most outside wall to fill.
  • Hollow block is rare here: 1.3% of Kilkenny's pre-2011 BERs, against 4.2% nationally. A block house here is more likely to be a true cavity wall, but only the survey can say.

Kilkenny and Ireland compared

KilkennyIrelandRank of 26
Households, Census 202236,6851,836,728
Built before 2011, inside the grant92%90%
Built 2011 or later7%8%10th
Detached houses59%41%11th
BERs for homes built before 201111,953751,700
Empty cavity wall3.7%4.5%19th
Cavity, part insulated29%28%16th
Hollow block1.3%4.2%13th
Rated E, F or G26%25%9th
BERs for grant claims per 1,000 pre-2011 homes, 202644.442.116th
Heating degree days a year1,9612,07915th

Households and year built: CSO Census 2022 (table F2007A), councils in the county added together. BER figures: SEAI BER Research Tool, the full public file downloaded 29 October 2026: 751,700 certificates for existing homes built before 2011, leaving out the BERs done for grant claims. Degree days near Kilkenny city: our sum from Met Éireann's 1991–2020 grid. Ranks are ours, 1st being the highest.

Next door, the share of pre-2011 BERs with an empty cavity wall: Laois 4.6%, Carlow 4.4%, Wexford 3.9%, Waterford 4.5%, Tipperary 4.4%. All 26 counties side by side.

The walls on Kilkenny BERs

The grant only pays where a cavity can be filled. SEAI's register holds 11,953 BER certificates for Kilkenny homes built before 2011, leaving out the ones done for grant claims. Their main wall:

Main wallKilkennyIrelandFor the grant
Empty cavity3.7%4.5%The job this grant pays for
Cavity, part insulated29%28%A survey decides: the 40 mm rule
Filled cavity21%16%Done. Second measure is internal or external
Hollow block1.3%4.2%Can't be pumped
Solid stone, brick or concrete13%14%No cavity: internal or external
Timber frame13%6%Can't be cavity insulated
Other or not recorded19%27%

Empty cavity: a 300 or 425 mm cavity wall with a U-value of 1.0 or more. Source: SEAI's BER register, as above. Our count.

11% of the Kilkenny cavity walls on those certificates have no insulation at all, against 14% nationally. Hollow block, solid and timber frame walls, 27% of Kilkenny's certificates against 24% nationally, can't take a cavity fill: SEAI's standards say cavity hollow block walls are not suitable and timber frame homes cannot be cavity insulated (SEAI technical standards). For those the grant routes are internal or external insulation, and our sister site covers external wall insulation in Kilkenny.

The size of the job is the wall. Of Kilkenny houses built before 2011, the commonest type is the detached house (Census 2022). On BERs the median detached house has 130 m² of outside wall, against 128 m² nationally, about the same. SEAI publishes its median costs nationally, not by county.

Home typeOutside wall, KilkennyIreland
Detached house130 m²128 m²
Semi-D89 m²91 m²
End of terrace87 m²85 m²
Mid-terrace51 m²48 m²
Apartment49 m²43 m²

Median wall area recorded on BER certificates for Kilkenny homes built before 2011: SEAI's BER register, as above. Our medians.

The only way to know your own wall is a survey: a small drilled hole and a borescope on each elevation, which SEAI's standards require before any fill (SEAI technical standards). Is my house suitable? has the checks you can do yourself first.

Heating, weather and grant claims in Kilkenny

The grant doesn't depend on the fuel, but the fuel decides what an empty cavity costs you each winter, and what the installer has to check. 54% of Kilkenny households heat mainly with oil (CSO Census 2022). An oil boiler needs its combustion air supply and flue kept clear, and the flue tested after pumping, as SEAI's standards require (SEAI technical standards).

Main central heatingKilkennyIreland
Oil54%39%
Natural gas21%33%
Electricity8%12%
Coal, peat or wood10%9%

Share of all households, including those that didn't state a fuel: CSO Census 2022, table SAP2022T6T5CTY.

Kilkenny city has about 1,961 heating degree days a year on Met Éireann's 1991–2020 averages, against 2,079 for Ireland (our sum, base 15.5°C). The heat a wall loses rises in step with that number. 26% of Kilkenny's pre-2011 BERs are rated E, F or G, against 25% nationally (SEAI's BER register).

Every SEAI home grant needs a BER after the work, so the BERs done for grant claims track finished grant jobs of every kind, walls included. In Kilkenny there were 1,047 in 2024, 1,159 in 2025 and 1,493 in 2026 up to 29 October: 44.4 per 1,000 homes built before 2011, against 42.1 nationally (SEAI's BER register).

The cavity wall grant by home type

The grant is the same in Kilkenny as in every other county: a fixed amount by home type, whatever the contractor charges. Homeowners on a qualifying welfare payment, and homes in an active HAP tenancy or RAS arrangement, get the higher rate.

Home typeStandard grantHigher rate: welfare, HAP, RAS
Detached house€1,800€2,300
Semi-D or end of terrace€1,300€1,700
Mid-terrace€850€1,100
Apartment€700€900

Source: seai.ie wall insulation page, checked 29 October 2026.

What's left after the grant, on SEAI's national median costs for January to June 2026. SEAI publishes no Kilkenny median, and we don't invent one:

Home typeMedian installed costSEAI grantTypical cost after grant
Detached house€2,350€1,800€550
Semi-D or end of terrace€1,585€1,300€285
Mid-terrace€1,250€850€400
Apartment€1,036€700€336

Costs: SEAI median costs, January to June 2026, from SEAI's median costs PDF (a sample of 23,412 completed upgrades; the cost each contractor submitted to SEAI at grant payment; VAT status not stated on the PDF), read 29 October 2026. Grants: seai.ie wall insulation page, checked 29 October 2026. One Irish cost guide gives €7.50 to €13 per m² including VAT (ShamFix, 31 July 2026).

  • A home built and occupied before 31 December 2010, with an MPRN
  • All external walls fully insulated: partial insulation isn't eligible
  • An SEAI-registered contractor, and SEAI's grant offer before work starts
  • An installer approved by NSAI for the system used

Two national registers, both searchable: SEAI's register of contractors, which the grant requires, and NSAI's register of cavity wall insulation installers, which SEAI's standards require for the system used. The rules in full: cavity wall insulation grant, cost, the job step by step and which wall grant fits.

FAQ

Kilkenny questions

Is the cavity wall grant different in Kilkenny?

No. SEAI pays the same fixed amounts in every county: €1,300 for a semi-D and €1,800 for a detached house, with higher rates for qualifying welfare recipients and HAP or RAS homes. What differs is the walls: 3.7% of Kilkenny's pre-2011 BERs record an empty cavity, against 4.5% nationally.

How many Kilkenny homes have an empty cavity wall?

3.7% of BER certificates for Kilkenny homes built before 2011 record an empty cavity with no insulation, the 19th highest share of the 26 counties. Another 29% record a cavity that's part insulated, which a borescope survey checks against the 40 mm rule.

Can every Kilkenny house with block walls be pumped?

No. 1.3% of Kilkenny's pre-2011 BERs record hollow block and 13% timber frame, and SEAI's standards rule out a cavity fill in both. A survey with a small drilled hole and a borescope tells you which wall you have.

How many Kilkenny homes are too new for the grant?

Census 2022 counted 2,473 Kilkenny households in homes built in 2011 or later, 7% of the total. SEAI's wall grants are only for homes built and occupied before 31 December 2010.

Who will ring me in Kilkenny?

One SEAI-registered contractor who covers Kilkenny. They survey the walls, check the cavity with a borescope and give you a written price with VAT. Nothing is booked until you say yes, and SEAI approves the grant before any work starts.

Your grant

Your cavity wall grant in 3 taps

Tap your home type, when it was built and any earlier wall grant. Your SEAI grant shows as you go. Then leave your number and one SEAI-registered contractor who covers your area rings you with a price.

What type of home is it?

SEAI pays a fixed amount for each type of home.

By sending, you agree to Cavity Wall Insulation passing your details to one SEAI-registered contractor who covers your area, so they can contact you about the job. cavitywallinsulation.ie is not SEAI or a government body and does not award grants. Privacy notice

Sources (1)

Prices and facts on this page were checked against these published pages. We are not connected to these businesses.

  1. ShamFix: shamfix.ie