Attic conversions and dormers in Ireland
Reviewed October 2026 · Not legal, planning or financial advice
An attic conversion adds space without losing any garden. Whether it adds a bedroom depends on whether it meets the Building Regulations for a habitable room.
Habitable room or storage?
Many Irish attic conversions are “non-habitable storage” because they don’t meet requirements for head height, stairs, fire escape or ventilation. A non-compliant room is not treated as a bedroom when the house is sold. If the goal is a bedroom, design to the Building Regulations from the start.
Head height and stairs
There must be adequate head height under the ridge — measure from the top of the ceiling joists to the underside of the ridge before going further. A proper stair takes space from the landing or a bedroom below.
Dormers and planning
Rooflights to the rear are often possible without planning permission. Dormer windows change the roof profile and generally require planning permission, and front dormers are frequently resisted.
Fire safety
Adding a habitable floor changes the fire-escape strategy for the whole house — typically requiring a protected stair route and fire doors. Get this designed, not improvised.
Regulations and their interpretation change. This guide explains the position as we understand it in October 2026. Confirm what applies to your house with an architect, planning consultant or your local authority before relying on it.