Kitchen and house extensions in Dublin
A single-storey kitchen extension in Dublin costs €1,800 to €2,500 per m² to build, including VAT. A 25 m² extension with a new kitchen and fees comes to €55,000 to €98,000 all in, standard to mid-range. Up to 45 m² at the back needs no planning permission if it meets the conditions.
Builders covering Dublin city, Swords, Lucan, Tallaght, Dún Laoghaire, Blanchardstown. What it costs here, the housing, and the council.
Free, no obligation. One local builder prices it, not five.
- €1,800–€2,500per m² in Dublin, incl. VAT
- €55,000–€98,00025 m² with a kitchen, all in
- 46 m²average extension given permission in Dublin, 2025
- 518,490households in Dublin (Census 2022)
Extending a house in Dublin
Dublin is the county of small gardens and terraces. 33% of Dublin households live in a terraced house, more than anywhere else, 30% in a semi-detached house and only 10% in a detached house. 27% live in flats and apartments, which can't be extended this way at all.
Extensions that need planning permission are smaller here. In 2025 Dublin's councils granted 2,502 permissions to extend homes, 35% of the national total, averaging 46 m² against 66 m² nationally (CSO). Small plots are why: on a city garden, the rule that 25 m² of open space must be left usually bites before the 45 m² does.
34% of Dublin homes were built between 1946 and 1980: the semis and terraces of Crumlin, Raheny, Artane, Walkinstown and Ballyfermot, with small back kitchens that are the classic case for a rear extension or a side return.
Building costs are highest here: €1,800 to €2,500 per m² for a single-storey extension, including VAT. Older parts of the city have more protected structures and architectural conservation areas, where the exemption may not apply. Ask the council first.
- 10%detached
- 30%semi-detached
- 33%terraced
- 34%built 1946 to 1980
What an extension costs in Dublin
| Type | Build cost in Dublin |
|---|---|
| Single-storey rear | €1,800 to €2,500 per m² |
| Side return | €2,000 to €2,700 per m² |
| Wraparound | €2,500 to €3,500 per m² |
| Two-storey | €2,200 to €2,800 per m² |
| High spec or glazed | €3,000 to €4,000 per m² |
- 20 m² single-storey rear, mid-range, with a kitchen: €58,000 to €85,000
- 30 m² single-storey rear, mid-range, with a kitchen: €80,000 to €110,000
- 40 m² wraparound, mid-range, with a kitchen: €135,000 to €175,000
All in means build, design and engineer's fees, and a mid-range kitchen, including VAT. Keep 12% to 15% aside.
For a new kitchen in the room you have, kitchenrenovationdublin.ie covers Dublin.
Plan your extension and see the cost
Nine quick taps. You see your plan build up as you go: the price range, what moves it, the planning position and the build time. Your number is only asked for at the end, if you want a real price.
A 25 m² single-storey rear extension in Dublin, mid-range, with wide glass doors and a new kitchen: €69,000 to €98,000 all in, including VAT and fees.
How this is worked out
We start from what single-storey extensions cost to build per square metre in each part of Ireland, including VAT at 13.5%, and the rates for side, wraparound, two-storey and heavily glazed extensions. Standard finishes take the lower half of the range, mid-range the upper half, and high spec or a wall of glass the glazed rate. Then we add professional fees (design, engineer, BER) and, if you want one, a new kitchen at your level of finish. Totals are rounded to the nearest €1,000. It's an estimate to plan with, never a quote: the builder prices your house after seeing it.
Planning in Dublin
The rules are national: up to 45 m² at the back with no planning permission, if it meets the conditions, since 27 July 2026. Planning applications in Dublin go to Dublin City Council and Dún Laoghaire-Rathdown County Council and Fingal County Council and South Dublin County Council. The fee for a house extension is €34, and a section 5 declaration on whether your extension is exempt is €80.
The exemption doesn't apply if the house's own planning permission has a condition that takes exempted development away (common on newer estates), if the house is a protected structure and the work would affect its character, or if the extension would obstruct a public right of way or a road. The full rules.
Every kind of kitchen extension
The costs, the rules and what to ask for, a page each.
Single-storey rearAcross the back of the house, usually with roof windows and wide glass to the garden.
Side returnThe narrow passage beside a terrace's back return, filled in and lit from above.
WraparoundAn L round the back and down the side, for one big kitchen, dining and living room.
Two-storeyA bigger kitchen below and a bedroom above, on one set of foundations.
Roof windows and lanternsFlat with roof windows, pitched, or a glazed lantern over the middle of the room.
Bifold or sliding doorsThe back wall opens to the garden. Which opens better, which seals better.Kitchen extensions by county
Each county page has its own housing figures, council and costs.
Dublin questions
How much does a kitchen extension cost in Dublin?
A single-storey kitchen extension in Dublin costs €1,800 to €2,500 per m² to build, including VAT. A 25 m² extension with a new kitchen and fees comes to €55,000 to €98,000 all in, standard to mid-range. Up to 45 m² at the back needs no planning permission if it meets the conditions.
Do I need planning permission for an extension in Dublin?
No planning permission is needed for a rear extension of up to 45 m², counting any earlier extensions built since 1964, if it meets the conditions: no higher than the house, at least 25 m² of private open space left, ground-floor windows at least 1 m from the boundary they face, and upstairs no more than 12 m² on a semi or terrace (20 m² detached). The limit rose from 40 m² on 27 July 2026. Applications go to Dublin City Council and Dún Laoghaire-Rathdown County Council and Fingal County Council and South Dublin County Council.
Do you cover all of Dublin?
Yes. Your request goes to one vetted builder who covers your county, including Dublin city, Swords, Lucan, Tallaght, Dún Laoghaire, Blanchardstown.
How big are extensions in Dublin?
Those that needed planning permission in Dublin averaged 46 m² in 2025 (CSO). Exempt extensions are up to 45 m².
Who will ring me?
One vetted builder who covers Dublin. Not a list. Nothing is agreed until you accept a written price.
Get a free quote for your extension
Plan it in under a minute, see the cost, and one vetted builder who covers your county rings you with a proper price.