A protected structure is a building or structure that a local authority has formally included in its Record of Protected Structures because it is considered to be of special architectural, historical, archaeological or other specified interest. Protection covers the structure, its interior, and normally its attendant grounds and other structures within its curtilage.
Under the Planning and Development Act 2000 (as amended), a protected structure is any structure that a planning authority has included in the Record of Protected Structures (RPS) forming part of its Development Plan. Structures can be added because of special interest under one or more of several headings set out in the Act, including architectural, historical, archaeological, artistic, cultural, scientific, social or technical interest. This is a broad definition, and it means protected structures range from grand country houses and churches to modest terraced cottages, industrial buildings, bridges and even street furniture, depending on what the local authority has assessed as significant.
Protection is not limited to the external facade or a single 'listed' building in the way some other countries approach heritage protection. In Ireland, if a structure is protected, the interior, the land lying within its curtilage (attendant grounds), and other structures within that curtilage, such as a coach house, gate lodge, garden wall or outbuilding, are normally also protected unless the Development Plan states otherwise. This wide scope is often misunderstood by owners who assume only the front elevation is affected.
Being a protected structure does not prevent an owner from living in, maintaining, or even altering the building, but it does mean that most works beyond normal maintenance require planning permission, and applications are assessed with particular regard to preserving the character and special interest that justified the listing in the first place.