Only Rolled Lead Sheet achieves the British Standard BS EN 12588 for thickness consistency.
The rolling process involves passing slabs of Lead back and forth between high pressured rollers.
The process is computer controlled to consistently obtain an exact predetermined thickness and knitted grain structure, allowing the performance of the product to be accurately predicted whilst in situ.
BS EN 12588 guarantees:A range of standard thicknesses with a tolerance of +/- 5%;
The alloy used conforms to quality of not less than 99.81% Lead;
Lead is produced to six standard Code thicknesses, The Code numbers were derived from the imperial weight of a piece of the Lead measuring 1 square foot. For example, Code 3 weighed 3lb per square foot. With the introduction of the British Standard, the emphasis changed to the thickness rather than its weight per area.