What is Spanish slate?
Spain is one of the biggest and most respected roof slate producing nations in the world, with a long tradition of excellence.
Every year, it exports millions of dollars worth of roofing materials to customers right around the globe.
In fact, it’s thought that as much as 90% of the natural slate in use today comes from Spain – most of it from the country’s slate-quarrying heartlands of Galicia, Castille and León.
Spanish slate is a type of metamorphic rock – formed deep underground over millions of years of intense heat and pressure.
Usually black or grey, it’s highly prized for its aesthetic qualities, and as a result, Spanish slate is an extremely popular choice on both new-build and refurbishment roof projects.
What is Brazilian slate?
Brazil is another major slate producing nation with a huge and rapidly growing slate export industry.
The vast majority of Brazilian slates come from Minas Gerais which is a state in the south-east of the country.
However, while the roofing material it produces is commonly referred to as ‘slate’, at a geological level it’s quite different to Spanish slate.
Brazilian slates are usually cheaper than Spanish slate but come with certain disadvantages
Rather than a metamorphic rock most Brazilian slate is mudstone which has implications for how it can be used.
Brazilian slate are less able to withstand the unpredictable British weather, especially in Scotland and frost damage and other phenomena like acid rain are likely to occur.
They can also be brittle and more likely to break than Spanish roof slate.
It’s the quarry that counts
However, when it comes to roof slates the country of origin isn’t everything.
Slate is a natural product – the result of hundreds of millions of years of heat and pressure – and unsurprisingly, that means the end results can vary drastically.
Slate from different countries, different regions, different quarries, even different veins of rock, will differ greatly. And some will be of a much higher quality than others.
But wherever a quarry is, it’s a fact that the majority of the material it produces won’t be suitable for roofing purposes.
Quarries cut, split and separate the slate roof tiles they produce according to a whole range of different factors – quality, appearance, thickness, and so on.
That means if we want really world-class natural slate, you need to find the right quarry – one with decades of expertise, and uncompromising standards as well as a lot of quality roofing material.
Introducing Del Carmen: world-class Spanish slate
At KBM, we’ve been sourcing world-class Spanish slate via SSQ from the Del Carmen quarry for over thirty years.
Located in North West Spain’s Cabrera Mountains, Del Carmen slate is prized worldwide – often hand-picked by architects for its distinctive, faintly-rippled texture, deep blue-black colour and longitudinal grain.
With quality controllers based practically on-site in their Spain office, SSQ are uncompromising about quality, ensuring their slate meets the most exacting international standards, and can trace all their products back to the source
What’s more Del Carmen Spanish roof slates have met and surpassed some of the world’s strictest quality standards – achieving the highest possible grades in US: ASTM C 406 and UK: BS EN 12326 testing, and passing the French NF 228 test, one of the hardest in the world.
This means that Del Carmen Spanish roof slates require extremely little maintenance, and will provide a lifetime of outstanding performance on any project or property.
In fact, in all the years Del Carmen Spanish slate has been installed in the UK, there’s not been a single registered failure of a Del Carmen roof.
That’s the benefit of working with a company that deals exclusively with one of the best quarries in the world.
At KBM via SSQ we’ve been providing the finest Spanish roof slates and array of other roofing materials to customers around Scotland.
If you’re interested in learning more, don’t hesitate to get in touch!
The Royal Institute Of British Architects report
National Federation of Roofing Contractors highlight the issues