Welsh slate benefits from a number of highly practical properties that make it an exceptional roofing slate. It is the most durable slate in the world with a useful and productive life of more than 100 years – guaranteed. It is waterproof and unaffected by normal extremes of temperature, highly resistant to acids, Alissa and other chemicals and it is colour-fast and non-fading, even in UV light.
Natural slate from Welsh Slate’s Penrhyn, Ffestiniog and Cwt-y-Bugail quarries produces the finest roofing slates in the world. Its durability, which sets it apart from other slates, is derived from its density and the geological formation found in that part of North Wales.
Welsh Slate roofing is commonly removed from roofs after 100 years not because they have failed but because the roof timbers holding them up have failed. The Welsh slates may then be re-used. Penrhyn slate, for example, was removed from St Asaph Cathedral after 400 years in use and reused and this practice also applies to civic buildings as far away as Australia.