SIGA Natural Slate sales director Robert Edwards discusses the company’s new website and how it can help architects achieve best practice for slate specification

In association with


SIGA Natural Slate

Natural slate roofing is a perennial favourite among architects and clients for good reason. It is hardwearing, aesthetically pleasing, and said to possess the lowest embodied energy of any roofing material. However, the sheer choice of products available combined with slate’s technical complexity can be challenging for specifiers. With this in mind, SIGA Natural Slate has launched its new website: Robert Edwards, Natural Slate and Core Specification Sales Director at SIGA Natural Slate, explains how and why the company has revamped its online presence, what new features have been introduced, and what the benefits are for architects.

Why has SIGA Natural Slate launched a new website and what are its aims?
In-depth research conducted among architects and specifiers indicated that the existing website lacked clarity when conveying technical information, and was not intuitive to use. The new site adopts a clear, single-platform approach, aimed at making natural slate products easy to understand and specify using simple and fast selection methods.


Slate is a natural product which varies in quality so specification can be a challenge. The SIGA brand gives specifiers confidence and consistency.

What are the principal features and innovations, and how are these intended to help architects?
There are five key areas SIGA Natural Slate has addressed.
• The first is better navigation through easily accessible product information, case studies, downloads and images.
• Second is improved product selection using SIGA’s new Product Finder.
• Third, is greater access to information about natural slate through our new Knowledge Base.
• The final two areas are concerned with providing comprehensive information on SIGA’s Heritage range of reproduction stone and slate products, as well as the SIGA brand itself.

How does the Product Finder work and what are its key features?
The main aim of the Product Finder is to enable specifiers to select the right slate product for their project, irrespective of how much – or little – prior technical knowledge they have. Slate selection can be problematic as the material is naturally occurring and therefore subject to wide variations in quality. This is compounded by the fact that there is currently no European or industry benchmark that allows specifiers to compare grades of slate from different quarries.


The SIGA Product Finder for natural slate: The Product Finder guides you through the range of slates available by project location, project type and other filters.

The Product Finder facilitates correct slate specification – from more than 20 different natural slate products spread over three ranges (Classic, Commercial and Excellence) – by identifying key project criteria. Specifiers simply select the appropriate building type, its geographical location, and a range of filter items, including slate texture, colour, size and length of warranty required. The Product Finder then automatically presents all the suitable products, allowing specifiers to make comparisons, investigate technical and performance details, and/or request samples.


SIGA Excellence slates on are ideal for heritage projects: here on Rassay House on the Isle of Skye

Crucially, each product is identified by a SIGA number relating to the quarry of origin and slate selection. This not only guarantees traceability – allowing SIGA to track slates from specification and order to delivery and on-site installation – but also ensures consistency. Close monitoring of quarry production and slate quality means that SIGA products/numbers can be removed or added to the site in real time, ensuring maximum transparency and ease of forward planning.


SIGA Natural Slate comes from certified quarries and mines worldwide, currently from Wales, Spain and the USA. The SIGA Number guarantees consistency and traceability.

What does the Knowledge Base contain and what new features are scheduled for 2019?
The Knowledge Base is conceived as a constantly growing and evolving information source aimed at specifiers and contractors. Users can sign-up and receive periodic article round-ups. At present, the Knowledge Base includes guidance on designing slate roofs, material on slate selection and testing, batten and holing gauges, coverage and fixings advice, headlap tables, on-site best practice, and frequently asked questions. SIGA will be adding information on its new low-pitch natural slate offer, which is due to launch soon. Future topics include, information on different types of slate mining, machine splitting versus hand splitting for slate fabrication, and material on how slates are graded.


The Natural Slate Knowledgebase aims to answer your common questions about natural slate

What is the Heritage range and what material is available on the website?
The new website has a product section dedicated to reproduction slate. This comprises three specific products: Heritage Reproduction Stone, Heritage Reproduction Reclaimed Slate, and Man-Made Smooth Square Edge fibre cement roofing slates.

Handcrafted and available in a choice of colours and sizes, Heritage Reproduction Stone is designed to provide a lightweight, durable and cost-effective alternative to Costwold stone, Collyweston slate and Swithland slate.


SIGA also produce a Heritage Range of reproduction stone and slate which provide approved alternatives to extinct types of local roofing stones and slates. Here: Cotsway – a genuine alternative to Cotswold Stone

Heritage Reproduction Reclaimed Slate eschews the challenges associated with traditional reclaimed slate – namely supply, quality and wastage – in favour of a handcrafted, glass fibre cement-based product that replicates the appearance of a weathered roof and is guaranteed for 25 years.

Last but not least, SIGA Man-Made Smooth Square Edge fibre cement roofing slates are conceived as a cost-effective alternative to natural slates. In common with SIGA’s natural slate products, the website provides clear and comprehensive information relating to performance, technical data and warranties on these ranges.

What additional information is there on the SIGA brand?
The new website covers the SIGA brand in much more depth. As one of the world’s largest suppliers of natural slate, we wanted to inform architects and specifiers about who we are, what we do and why we are the supplier of choice. SIGA also wanted to demonstrate is capabilities, particularly in the areas of mining expertise, consistency of supply and stringent quality control. The latter ensures that only the highest quality S1, T1 and W1 slates are imported to the UK from SIGA’s quarries.


SIGA 112s from the Excellence range was used in these new homes at St James Park, Didsbury

What response has SIGA received on the new website?
The initial feedback has been very positive, with users finding the website much more accessible and responsive to their needs. Most importantly, it is streamlining the specification process and serving as a valuable resource for all aspects of natural slate roofing.

Contact Details
SIGA Natural Slate has a team of specification experts you can contact direct via the website. Alternatively, try out the Natural Slate Product Finder for yourself here: