Roofing

Welsh Slate Roofing

Welsh Slate is recognised as the best quality roofing slate in the world, and will give you a roof that will last more than a lifetime.

This is because its extraordinary geology gives it unique physical properties which, when combined with generations of skilled quarrymen, create a roofing slate which has been tested over the centuries by the harshest climates imaginable. Available in three thickness grades: Capital; County; and Celtic; to suit the projects requirements. If you need help in understanding the precise benefits a Welsh Slate roof will provide then please call us - we'll be happy to explain more.

 

Why the unique geology of Welsh Slate makes it the best natural roofing slate

Welsh Slate was laid down as a sediment some 550 to 470 million years ago, heated and compressed by the same huge tectonic forces that created the Snowdonia mountain range. The resulting unique raw slate material contains no reactive minerals and it is this, combined with its ability to be split into very thin flat sheets, that make it the ideal roofing slate. This is because it is light weight, extremely durable and has a natural beauty which only gets better with time. This is why Welsh Slate has been the roofing choice of the world for centuries.

Welsh Slate roofing product is only available from two quarries, each quarries product retains the unique physical characteristics but has its own individual, distinctive natural colouring;  Penrhyn® - a Heather Blue slate, and Cwt-y-Bugail - a dark blue grey slate.

The beautiful colours of Welsh Slate Roofing

The subtle and elegant colours of the Penrhyn® Heather Blue slate, and the Cwt-y-Bugail dark blue grey slate, are further enhanced by the distinctive natural texture of each slate. This creates an added dimension to any roof whilst the combination of colours can be used to create a pattern or subtle contrast in a design.

The aesthetic qualities of Welsh Slate are combined with the material’s natural durability and resistance to weather and temperature, making slate superbly adaptable and ideal for all environments.


Heather blue slate

Penrhyn® Heather Blue slate, known also as Bangor Blue and Penrhyn® Purple.

This is produced from a fine-grained slate deposit laid down over 500 million years ago in the Cambrian period and comes from the Penrhyn® quarry. Set in the heart of Snowdonia, it's one of the largest slate quarries in the World, and has been in commercial production for over seven centuries. The properties of the Penrhyn® slate allow it to be split into thin sheets but still retain its strength and unparalleled durability.

Penrhyn® slate comes in three thickness grades: Capital, County, and Celtic, to suite each design, to suit specific roofing needs.

View Penrhyn® Welsh Slate

Dark blue grey slate

Cwt-y-Bugail Welsh Slate is dark blue grey in colour with a distinctive texture which makes it a popular architectural material.

This is produced from the Ordovician slate beds laid down over 470 million years ago and comes from the Cwt-y-Bugail slate quarry in Ffestiniog, North Wales. It has been producing slates from 1840, and is currently the highest industrial site in the UK. The slate has a distinctive banding known as relic bedding and gives an extremely uniform unfading appearance on the roof.

Cwt-y-Bugail slate comes in three thickness grades: Capital, County, and Celtic, to suit each design, to suit specific roofing needs.

View Cwt-y-Bugail Welsh Slate

Striking designs

Many architects choose to combine the purple tones of the Penrhyn® Heather Blue slate, with the dark blue grey of the Cwt-y-Bugail Welsh Slate.

Creating a striking design using the contrasting colours and textures, ensures the architectural features of the roof make it standout from the skyline.

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Welsh Slate Roofing Manufacturing Process

The manufacturing of Welsh Slate roofing remains a hand-crafted process using traditional skills and techniques developed over centuries. This is carefully combined with modern production processes to ensure all our roofing slates are of the highest standard. Slates are then dressed to their final size with traditional chamfered edges, graded for thickness and packed for despatch.

The focus of production is on the core sizes (Penrhyn; 500 x 300 mm, 400 x 250 mm & 300 x 200 mm. Cwt-y-Bugail; 500 x 250 mm, 400 x 250 mm & 300 x 200 mm) but it has the flexibility to produce bespoke sizes to order.

 

Welsh Slate Roofing thickness grades

Welsh Slate roofing product is available from two quarries, Penrhyn (Heather Blue/purple slate) and Cwt-y-Bugail (Dark Blue Grey slate), in three thickness grades: Capital, County and Celtic to suit the project requirements. If you need help in understanding the precise benefits a Welsh Slate roof will provide then please call us - we'll be happy to explain more.

Capital Grade Welsh Slate

Capital Grade is the thinnest production Cwt-y-Bugail Welsh Slate at 5.5 mm.

Only limited parts of our quarries will make this slate with its fine-grained riven surface. The thinness of the slate gives a flat uniform finish to the roof and was traditionally the material transported to the more distant markets such as continental Europe and even as far away as Australia and New Zealand.

County Grade Welsh Slate

County Grade is the main production thickness at Welsh Slate at 7 mm thick.

The surface texture is similar to the Capital Grade, but the slightly thicker leading edge gives more focus to the slate on the roof. Traditionally sold in the Midlands and North West of England, it is now sold widely across the world.

Celtic Grade Welsh Slate

Celtic Grade is the thickest of Welsh Slates production at 9 mm.

As its name suggests, its natural home is on the roofs of buildings facing the prevailing westerly winds in Ireland, Scotland and Wales. The more textured surface and thicker leading edge give the slate a more rural appeal but the Celtic Grade slate does find its way into city centres, where it can be used to make a statement: There is no doubt that this is a natural slate roof.


Benefits of Welsh Slate roofing

It's Welsh Slate's unique geological factors which makes Welsh Slate unlike any other natural roofing slate available in the world.

Where other slate quarries and producers make roofing product, they cannot have the natural qualities of Welsh Slate, which is probably why they have multiple standards, making it confusing to identify the precise durability and quality of the product on offer. Welsh Slate roofing has only one standard - the very best - any slate that does not make the grade does not become a roofing slate.

  • Aesthetically pleasing - its natural tones work with any colour pallete
  • Colour-fast - your roof colour will look as good in 100 years as it did the day it was finished
  • The most durable slate in the world - with a useful and productive life of more than 100 years – guaranteed
  • UK manufactured by highly skilled quarrymen - which means only a low level of on-site grading is required, saving time and money
  • Unaffected by normal extremes of temperature - ideal for areas with harsh night frosts and fierce daytime sun
  • Highly resistant to acids, alkalis, and other chemicals - highly practical properties that make it an exceptional roofing slate
  • Large format sizes available - making Welsh Slate roofing slate much desired for heritage and prestigious projects

 

It is the only roofing slate to have a lifespan measured in centuries.

Making Welsh Slate 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, alkalis and other chemicals and it is colour-fast and non-fading, even in UV light.

Direct to you

Anyone can buy Welsh Slate direct, whether you are a home owner, developer or specifier.

If you need some help or advice you can speak with our customer services team on (+44) 01248 600656. If you want the best price on smaller quantities then visit our online sales store www.ukstonedirect.com or click below to find out more.

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