We’ve talked heavily about the differences between machine cast lead and rolled lead sheet over the past few months. This has been, in part, down to our recently commissioned industry survey, which revealed widespread confusion and misunderstanding around the differences between the lead sheet types among lead merchants and end users.
The facts are that lead sheet, whether produced through a machine cast or a rolled manufacturing method, is remarkably similar, sharing many attributes.
Both are made from 99.95% pure, recycled lead; both are manufactured using the exact same chemical specification; and both are made according to the same analysis, codes, tolerances and permitted sizes. Consistency in thickness is also identical, varying by more than +/- 5% at any given point.
BBA celebrate 50th anniversary
The differences, rather than in the actual product, lie in warranty, the way in which the product is manufactured and, of course, accreditation. And with the British Board of Agrément celebrating its 50th anniversary this year, we thought now was the perfect opportunity to focus on the accreditations side.
High quality machine cast lead has a British Board of Agrément 86/1764 accreditation, while high quality rolled sheet has a British Standard 12588.
British Standard (BS) tends to have higher awareness than British Board of Agrément (BBA) in the construction industry, leading to the opinion that BS is better than BBA.
In fact, BS 12588 and BBA 86/1764 share the exact same standard requirements, however, the BBA benefits from additional requirements, including twice annual external surveillance visits and a 3-year review on product quality and service levels, as well as internal quality checks. BBA-accredited machine cast lead also carries a 60-year warranty, while BS-accredited rolled lead offers 50 years.
Both BBA and BS-accredited lead sheet is also accepted by the NHBC, Building Control, architects, designers and engineers, insurers, building associations and all local authorities and government bodies throughout the UK.
Established in 1966, the BBA says it is proud to have worked with some of the most esteemed companies in the construction industry and to have carried out assessments and approval of a variety of revolutionary construction solutions.
Phil Bloomfield, Commercial Director, BBA, says: “A BBA certificate often relates to an innovative element of manufacture. But innovative process or not, our approval is granted only if a product has a level of performance at least as good as, or better than, that specified by the BS. And that’s the case with Midland Lead’s cast lead.”
While machine cast lead does in fact conform to the British Standard 12588 specification, it is currently impossible for machine cast lead, no matter how high quality standards are, to qualify for it, as it is only applicable to lead manufactured through a milling process.
Whatever your preference, as the only UK lead manufacturer to offer the entire range of lead products, including machine cast, rolled and sandcast lead sheet, we always recommend thoroughly researching products, so that you can make better, more informed decisions for your customers or project.
Download our infographic for full details.