Penrhyn Bangor Blue Slates on Armagh Cathedral
Residential Self-Build

Conservation & Heritage Projects

Welsh Slate (Blue Bangor Slates) has been coming into Ireland for the past 600 years but it was during the late Georgian and early Victorian era when these slates really left their lasting mark on Irish architecture. Many of Ireland’s most prestigious and landmark buildings from around this period were roofed with slates from the Penrhyn Quarry. Some notable examples include Dublin Castle, St. Patrick’s Cathedral and Castletown House in the South and Armagh Cathedral, Hillsborough Castle and Belfast Castle in the North.

It was common at this time for the slates to be large format and random in size and there are many 24”, 26” and even 36” inch slates from this period. At this time the slates were given names such as Kings, Queens, Duchess’, Countess’ etc. Although today the quarry tends to make slates to a standard 500x300mm size, it still has the capacity to produce larger format slates for Conservation & Heritage Projects when the architect wants to replicate the original size of slate that went onto the building originally. Some recent examples of where the quarry has produced larger sized slates recently for conservation purposes include the re-roofing of Clonard Monastry and Crumlin Road prison in Belfast, Castletown House in Kildare and the Holy Cross Church in County Waterford.

It is down to the unique characteristics and exceptional quality of Welsh Slate that lends itself to being able to split into these sizes and Penrhyn is the only slate quarry in the world that can produce these large format sizes.