Penrhyn Bangor Blue® Roofing slates are universally acknowledged as the best quality roof slate in the world. These slates have a lifespan measured in centuries and a second hand 150 year old Welsh Slate has a sales value of one third of a new slate!
So why is it that these slates are the best in the world? There are a number of reasons:
- Penrhyn Slate deposits date back to the Cambrian era which is over 600 million years ago (a period in time when marine life was just starting to evolve). Most 'imported' slates on the market come from the Ordovician era (some 400 million years ago). So Welsh Slates are 200 million years older than most imported slates and, as a result, they have a much harder and denser composition.
- The quality of the original sediments which formed the slate was extremely pure. There are no damaging inclusions or pyrities in Penrhyn Slates which you may find in slates from other parts of the world.
- Welsh Slate is chemically inert to acids, alkalis and other chemicals.
- Welsh Slate does not change colour or fade.
- Welsh slate has an extremely low water absorption rating (0.13% against a European benchmark of 0.6%) and is effectively non porous - this is one of the key reasons why it outlives other slates.
- Welsh Slate is extremely strong and durable. It has a density rating of 2.8 tonnes per cubic metre which makes it denser than most granite.
- Low carbon footprint. These slates are made and manufactured in the UK and the quarry operates within strict environmental policies.
- There is minimal wastage/grading issues with these slates.
- These slates have been used as a roofing material since the 13th century and are proven to outlive all other roofing slates!