Non-habitable protected structures may pose different conservation problems to other structures because of the nature of their construction or use. Some frequently encountered types are dealt with in this section. Where proposed works under consideration concern the repair of structures, the appropriate methods are described elsewhere in these guidance notes.
Ruinous Buildings
There are many ruinous structures throughout the country including a variety of building types such as castles, houses, churches and cottages. Proposals concerning works to such structures are likely to fall into one of three types:
a) proposals to demolish the structure;
b) proposals to consolidate the ruin, or
c) proposals to restore the ruin and bring it back into use.
In the case of ruins which are recorded monuments in addition to being protected structures, it should be noted that there are separate additional procedures under the National Monuments Acts for notification to the statutory authority to be followed.
Consolidation of ruinous buildings
There are cases where a structure of definite architectural, artistic or historical interest, such as a ruinous tower house, country mansion or church, cannot be restored and brought back into use without compromising its special interest or character. This will often be the case with structures which have stood for a considerable time as ruins. In order to prevent further deterioration of the protected structure, it may be proposed to consolidate the fabric as it stands and to preserve the structure as a ruin
It should be a condition of permission for works to consolidate a ruinous structure that the methods used would not cause unacceptable damage to the character of the protected structure or an undue loss of historic fabric. The methods and detailed specification should be approved by the planning authority before any works commence. In some cases, even the removal of ivy or other vegetation from a ruinous building may have consequences for its structural stability and proposed methods of work should be carefully scrutinised
Proposals may be made to take down and re-erect all or part of the walls of a ruinous structure where the walls are failing. Such proposals should generally only be permitted where it can be shown that the structure is in danger of collapse and no other option is available. It should be a condition of permission that the structure be fully recorded before dismantling is allowed to commence and be rebuilt using a maximum amount of the original material. In cases where there is good quality masonry, the stones should be individually numbered before being carefully dismantled to be re-erected in the same location
In the consolidation of ruinous structures, attention needs to be paid to wall tops and openings as these areas are most vulnerable to water penetration and frost attack. However, works should not damage the fabric and appearance of the protected structure. The use of hard cement-based mortars may trap water against the surface of the wall or within the core of the wall and so promote decay. Where it is proposed to provide added protection to exposed parts of the ruin in the form of copings, flashings or mortar, these should not damage the fabric or appearance of the structure. Similar consideration should be given to proposed flashings which turn down over mouldings, cornices or the like and may unacceptably distort the proportions of the moulded work.
