How much does an attic conversion cost in Ireland?
An attic conversion in Ireland typically costs €18,000–€45,000 in 2026, depending on whether it's a simple storage-and-room conversion or a full dormer with new stairs, insulation, windows and a bathroom. It's one of the most cost-effective ways to add usable space without extending the footprint of your home.
This guide covers realistic prices by conversion type, what affects the cost and the building rules that decide whether your attic can become a true habitable room.
Typical attic conversion costs in Ireland (2026)
| Job | Typical price |
|---|---|
| Basic room conversion | €18,000 – €28,000 |
| Conversion with new stairs & rooflights | €25,000 – €38,000 |
| Dormer conversion | €35,000 – €55,000 |
| Adding an en-suite | €4,000 – €9,000 |
| Velux roof window (each) | €900 – €1,800 |
Prices are typical 2026 estimates and vary by job, condition and location.
What affects the cost?
- Head height — low roofs may need a dormer or raised ridge, which costs more.
- Stairs — a compliant fixed staircase takes space and money.
- Insulation and fire safety — upgrades are needed for a habitable room.
- Windows — rooflights are cheaper than dormer or gable windows.
- Plumbing — adding a bathroom raises the price significantly.
Can my attic legally become a bedroom?
To be called a habitable bedroom, an attic conversion must meet building regulations for head height, fire escape, insulation and a compliant staircase. A pull-down ladder isn't enough. If it doesn't meet these standards it can only be described as a storage or hobby room, which matters when selling.
Do you need planning permission?
Most internal attic conversions are exempt from planning permission, but adding a large dormer, changing the roof profile or working on a protected structure can require it. Always confirm with your local authority before starting.
Frequently asked questions
How much does an attic conversion cost in Ireland?+
Most attic conversions cost €18,000–€45,000 in 2026, depending on whether it's a basic room or a full dormer with stairs, insulation and a bathroom.
Do I need planning permission for an attic conversion?+
Most internal conversions are exempt, but dormers, roof-profile changes or protected structures may need permission. Check with your local authority.
Does an attic conversion add value to a house?+
Yes — a compliant attic bedroom usually adds meaningful value, often more than its cost, especially in areas where space is at a premium.
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