Roof insulation by county
Insulating an attic floor costs €1,800 to €2,101 for a semi-detached house and €2,400 to €2,700 for a detached one, before an SEAI grant of €1,500 or €2,000. Insulating a room in the roof at the rafters, with a plasterboard finish, runs €100 to €180 per m², and a warm flat roof with a new membrane €130 to €190 per m². VAT is included.
How every county's roofs are insulated now, from the BER certificates, with its climate.
Free and no obligation. Your plan goes to one contractor, not a list.
- 26counties
- 35%meet the standard in Monaghan, the most
- 16%in Dublin, the fewest
- 24%nationally
Plan your roof insulation
A few quick taps, and your plan fills in as you answer: the right method for your roof, what it costs, the grant and the standard to ask for. Contact details come last, and only if you want a contractor to price it.
Attic floor insulation, semi-d or end of terrace: €1,800 to €2,101 before the €1,500 SEAI grant, so about €300 to €601 to pay.
How the estimate is worked out
Attic floor insulation uses what SEAI-registered contractors were paid for each kind of home in 2026 and what an Irish installer charges, with the SEAI grant taken off. A room in the roof and a flat roof are priced per m² of the area you enter: rafter boards with a plasterboard finish, or a warm roof with a new membrane. VAT is included. Use it to plan with. It isn't a quote: a contractor prices your roof after a survey.
All 26 counties side by side
From BER certificates for houses built before 2011, and Met Éireann's 1991 to 2020 temperatures.
| County | Meet 0.16 | Middle U-value | Middle roof area | No insulation | Degree days |
|---|---|---|---|---|---|
| Carlow | 28% | 0.26 | 64 m² | 6% | 1,969 |
| Cavan | 28% | 0.25 | 72 m² | 7% | 2,159 |
| Clare | 29% | 0.26 | 73 m² | 6% | 1,843 |
| Cork | 25% | 0.27 | 60 m² | 9% | 1,755 |
| Donegal | 24% | 0.26 | 75 m² | 6% | 2,211 |
| Dublin | 16% | 0.40 | 53 m² | 8% | 1,825 |
| Galway | 29% | 0.26 | 74 m² | 6% | 1,860 |
| Kerry | 27% | 0.26 | 76 m² | 7% | 1,673 |
| Kildare | 23% | 0.26 | 65 m² | 4% | 2,093 |
| Kilkenny | 27% | 0.26 | 69 m² | 6% | 1,961 |
| Laois | 32% | 0.25 | 66 m² | 5% | 2,080 |
| Leitrim | 21% | 0.26 | 74 m² | 9% | 2,102 |
| Limerick | 28% | 0.26 | 64 m² | 8% | 1,837 |
| Longford | 31% | 0.25 | 69 m² | 6% | 2,094 |
| Louth | 26% | 0.26 | 59 m² | 6% | 1,951 |
| Mayo | 26% | 0.26 | 80 m² | 9% | 2,028 |
| Meath | 25% | 0.26 | 70 m² | 5% | 2,048 |
| Monaghan | 35% | 0.23 | 64 m² | 8% | 2,182 |
| Offaly | 31% | 0.25 | 68 m² | 5% | 2,046 |
| Roscommon | 24% | 0.26 | 81 m² | 11% | 2,088 |
| Sligo | 26% | 0.26 | 65 m² | 7% | 2,032 |
| Tipperary | 31% | 0.26 | 67 m² | 9% | 1,959 |
| Waterford | 27% | 0.26 | 62 m² | 7% | 1,781 |
| Westmeath | 25% | 0.26 | 66 m² | 6% | 2,162 |
| Wexford | 23% | 0.26 | 72 m² | 7% | 1,844 |
| Wicklow | 17% | 0.34 | 67 m² | 7% | 1,883 |
County questions
Which counties do you cover?
All 26. Your plan goes to one vetted insulation contractor who covers your county.
Are the grants the same in every county?
SEAI's individual grant for roof insulation is for the attic floor: €2,000 for a detached house, €1,500 for a semi-D or end of terrace, €1,400 for a mid-terrace and €1,100 for a top-floor apartment, with higher amounts for first-time buyers of an older home and some people on welfare payments. Rafter and room-in-roof insulation are grant-aided only as part of a One Stop Shop whole-home upgrade.
Every guide and county page
Methods
Costs, grants and rules
Keep the heat under your roof
Pick the roof, what's there now and the home to see the method and the cost. When you want a firm price, your plan goes to a single vetted insulation contractor for your area.