mburke,
If the house is substantially complete - i.e. with structure and envelope relatively intact - regardless of leaks, etc. - and disregarding when it was last occupied, it is efffectively an empty pre-63 house.
Many rural villages possess these, and you canmake a case for its continuance on historical and "village fabric" grounds alone, without even getting into its substantially complete situation.
In terms of the legalistic reference SUperman makes, I agree with him.
There was a provision in the original Planning and Development Act 2000 wherein under the then enforceable "2-year" permissions, IIRC houses would not be subject to enforcement proceedings to complete if they were up to wall level - please could someone correct me if I am recalling this incorrectly?
This led to the position that once a house was complete up to wall plate level [i.e. the walls were standing] - an application for continuance of the permission to allow completion if it was near the end of the five year Grant period, would not be unreasonably withheld.
It follows that four walls may have a standing in law in relation to your house.
More importantly several local authorities, desiring new blood and renewal of housing stock, [e.g. Donegal Co. Co.] have taken a view - expressed in their development plan - about the restoring and rebuilding of residential property, in several states of disrepair and despite intervening years.
However there is usually a tie-in to the area required for one or more of the applicants, but you should fully research the development plan and talk to the planners before you go near this.
As RKQ has said, there can be associated requirements as well which can prove difficult to satisfy.
ONQ
[broken link removed]
All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.