Although demand for premium natural roofing slate is strong, you need to make sure you get what you pay for.
There’s no substitute for quality and this is certainly true with slate. However, the use of lower-grade slates which don’t meet British Standards and are sometimes being sold at premium prices persists. T2 and T3 slates are graded like that for a reason and no-one wants to pay top price for a product that isn’t up to scratch, so let’s just remind ourselves of some of the pitfalls of using a lower-quality option.
In terms of quality testing for compliance with BS EN 12326:2014, T2 slates show signs of oxidation or appearance changes of the metallic inclusions that may cause staining, pitting and/or delamination and potential failure of the slate in as little as three weeks. Even to the trained eye, inferior slate may be riddled with inconsistencies and imperfections that can affect its durability and performance over time, resulting in increased wastage and labour costs. Quite simply the NHBC prohibits these slates, the lifetime performance is less and the chain of custody isn’t as reliable.
All of this paints a pretty convincing picture as to why opting for a lower-quality slate is always going to be a false economy in the long run. Moreover, if there are any problems or issues with the job further down the line then you may incur additional costs at your own expense. The good news is that by using a reputable supplier like SIGA Natural Slate you avoid all of that in one fell swoop.
THE GOOD STUFF
SIGA were the first major distributor to discontinue T2 slates back in January 2016, that means ALL SIGA slate is T1:
- They are fully compliant with CE and Construction Products Regulations
- Come with warranties of up to 75 years that offer the assurance of consistent quality and full traceability, from the quarry to the roof
- Comply with any environmental and carbon footprint policies
- Full traceability fulfils a much more fundamental requirement if identical slates are ever needed in the future for redevelopment, refurbishment or extensions
It’s also worth noting that in 2009, the National House Building Council (NHBC) took the decision to recommend only T1 slates, and went so far as to ban the use of any other grade, such as T2, on new builds.
If that wasn’t enough, with T1 slate you get much lower wastage rates, which in turn means lower labour costs and faster completions. On top of that SIGA provide a level of technical support, datasheets, CPDs and health and safety advice that is second to none.
The moral of the story? You don’t always get what you pay for with slate. Unless that is you use a supplier like SIGA. In which case you most certainly do.