At verges and side abutments, Tile-and-a-Halves must be used in alternate courses with Concrete Plain, Heathland and Rosemary Clay Tiles. A unique manufacturing process on a bespoke production line enables the Rosemary Clay Craftsman clay tile, to be produced with a heritage look while maintaining all the attributes and strength of a brand new tile. 2014 marked the 175th anniversary of the first-ever Rosemary tile being sold on the UK market. Since that day Rosemary clay tiles have become inextricably-linked with Britains vernacular architectural style. Hawkhurst and Albury have a fine orange-red sanding over the surface and random black patterning to imitate a weathered look. The newest edition to the range, Victorian, has a darker and grittier texturer than the original Albury and Hawkhurst colours, giving roofs a greater depth of texture and character. Each Rosemary Craftsman tile has a textured surface and underside combined with textured sides and front edge. Other characteristics are the irregular front edge distortion and varying hanging length. All these features combine to accurately replicate the look of genuine handmade clay tiles. Properties Nail size: 40mm x 2.65mm - aluminium alloy nails. Tile finish: sanded. Tile profile: clay plain tile. Certification BBA certified. Rosemary Craftsman Clay Plain Tiles conform to BS EN 1304: 2013 Clay roofing tiles and fittings - Product definitions and specifications.