St. Mary's Pro-Cathedral, Marlborough Street, Dublin 1
EXPP: PROTECTED STRUCTURE: The works for which a declaration of exemption at St. Mary's Pro Cathedral is sought are: 1. Roofs 1.1 It is proposed to carry out urgent repairs to the naturally slated pitched roofs. In principle, these works are routine maintenance and are required to prevent potential source of water ingress posing a risk to the structure and interior building fabric. The scope of repair is to re-bed slipped hip and ridge tiles, re-fit slipped slates using copper nails or lead tinges as appropriate, local replacement of broken or missing slates with Welsh Bangor Blue slates to match existing slates as closely as possible in terms of size and coursing details, retain existing rooflights where present and carry out necessary repairs to rooflights, and flashings on a like for like basis. 1.2 It is proposed to carry out urgent repairs to the copper lantern and dome roofs. Rainwater has been observed to be entering into the cathedral interior from the copper lantern. In principle, retain existing covering, carry out necessary repairs to flashings and abutments on a like for like basis. 1.3 Treat vegetation growth and clear debris from gutters and outlets. 1.4 Roof repairs to NSAI Code of Practice for Slating and Tiling S.R.82:2017, and Copper Development Association Inc's guidance document 'Copper in Architecture - Design Handbook' (2024). 2 Second Floor Level: 2.1 It is proposed to carry out essential repairs to localised areas of the ceiling in two storerooms situated on the southern side at second floor level where it appears that leaks have occurred and there is possible timber decay of structural roof members. The scope of repair is to expose localised area of ceiling to allow inspection of structure (approx. 300x300mm), carry out appropriate repair if required, and repair ceiling on a like for like basis. 2.2 From a review of the archival records, it is understood that during the 1980's & 1990's works were undertaken to strengthen timber floor joists at the second floor over the apse area. It is proposed to lift floorboards in four localised locations to allow for inspection of the timber joists ends where the bear into the masonry wall. Following inspection, the existing floorboards are to be reinstated on a like for like basis. 3 Ground Floor Level: 3.1 From a review of the archival records, it is noted that the columns between the nave and aisles are described as ''metal cylinders'' in historic records. The scope is to expose a localised area on the face of one of the columns to allow inspection of the structure (approx. 200x200mm), following inspections, repair face of column on a like for like basis. 3.2 From a review of the archival records, it is noted that the original floor finish in the Cathedral was York stone flags, and due to the extension of the building and degradation the stone floor was replaced with decorative mosaic in 1952. In the 1970's, a subsequent redecoration project was undertaken, which saw the decorative mosaic replaced, except for an area at the main entrance, central aisle, and area in front of the altar which were retained, and all remaining areas replaced with a plain mosaic. The desire of the proposed works would be to reinstate a stone floor, restoring the character of the protected structure (subject to planning permission). To investigate this, it is proposed to expose a localised area of the 1970's mosaic floor in the side aisle to examine the structure to determine if the existing condition can take a new stone floor or how it could be reinforced. The scope is to carefully lift the mosaic floor finish and substructure to allow for inspection of the structure over the masonry arches to vault area below (approx. 300mm wide x 2000mm long to expose spring and head of arch), following inspection the void will be backfilled and a suitable floor covering provided. 4 Basement Floor Level: 4.1 From a review of the archival records, it is noted that the cobble floor finish within the crypt space at basement level has been slid on made up ground, most likely Marley soil, which was common practice at the time, but it is suspected that the soil has broken down over the lifespan of the cathedral. It is proposed to expose a localised area of the crypt floor in the side aisle to examine the build-up and water table level to determine the existing condition. The scope is to carefully lift the existing floor finish and had excavate the made-up ground to assess the water table level (approx. 600x600mm and to a depth necessary to determine the water table level without undermining the existing walls), following inspection the void will be backfilled and the floor covering reinstated. 5 External Works: 5.1 The 21st C flush external double doors to the crypt on the south side of the site are in poor condition. The doorset shows signs of corrosion. It is proposed to replace the doors with louvered metal doors, to match the size and opening sections of the existing. The louvered design of the replacement doors will assist with natural ventilation to the crypt and moderating the high moisture levels. 5.2 Carefully lift and relay a select number of paving slabs that have become displaced at podium level to the south-east area. Are the above works considered exempt development?