The Armouredstone roofing system is a breakthrough in natural stone roofing, combining timeless aesthetics with cutting-edge performance. With its innovative and patented design, it delivers a lightweight, cost-effective solution that allows natural stone roofs to be installed on pitches as low as 17.5° — something not possible with traditional stone roofs, which typically require a minimum pitch of 35° to stay waterproof.
Product Composition
Each tile is crafted from premium natural limestone, cross-laminated onto a fire-resistant GRP (glass reinforced plastic) backing. This advanced GRP plate replaces the lower double lap layers of traditional roofing and hooks easily over the batten, providing full waterproofing at low pitches.
The GRP also features a patented water bar for precise placement, along with an extended side lap that integrates seamlessly with neighbouring tiles. Two parallel rows of high-performance EPDM tape create a permanent, watertight seal between each tile.
Proven Performance
In independent testing to BS PD CEN/TR 15601 standards, the Armouredstone system clearly outperformed conventional stone roofing. While traditional stone roofs require a minimum 35° pitch to stay waterproof, the Armouredstone system offers reliable waterproofing from just 17.5°.
In addition, the system uses 43% less stone, delivering a lighter, more efficient roof without compromising on strength or durability.
Simplified Installation
The Armouredstone system simplifies the complex process of installing random and diminishing stone roofs. It uses just three tile widths — 300mm, 450mm, and 600mm — all at a uniform length of 450mm.
This intelligent sizing makes it easy for installers to achieve the traditional broken bond pattern, where vertical joints (perp joints) are staggered. With a minimum overlap of 75mm, the system achieves a maximum exposed surface margin of 375mm (around 15 inches), replicating the proportions of a classic 36-inch slate.
Importantly, the single lap design eliminates the need for large, heavy stones and reduces the level of skill required for installation — cutting both time and labour costs.
Design & Appearance
Armouredstone delivers the look and feel of a heritage roof without the challenges of traditional stone. It is accurately colour-matched in beige to blend invisibly with the stone, though technical diagrams may show white purely for illustration purposes.
The system includes a matching, preformed, dry-fix ventilated natural stone ridge, available in 90°, 105°, and 120° angles. Bespoke ridge options are available upon request to suit specific roof designs.
Heritage & Reclaimed Applications
The Armouredstone system is ideal for both new and heritage projects. It can be paired with reclaimed or recycled stone slates, allowing old roofs to be upgraded with 43% less material while maintaining their original appearance.
Reconstituted stone slabs can also be used, offering a lightweight, cost-effective alternative that still achieves the look of aged stone. The system integrates seamlessly with reclaimed stone using the ‘Armouredstone Reclaimed’ system, making it perfect for conservation projects where authenticity matters.
Innovation Behind the System
Developed from years of research and innovation, the Armouredstone system was designed to address the main limitations of traditional stone roofing: heavy weight, steep pitch requirements, and the need for highly skilled installation. By combining genuine limestone with advanced GRP technology, the system provides a modern alternative to concrete and traditional stone — offering long life, stunning appearance, and high performance at a competitive price.
