Preventing disasters shown below will at last become controllable later this year when EN13914-1 becomes incorporated into British Standards. This Standard permits only PVCu, galvanised steel powder coated with plastic sleeve, or stainless steel to be used in external situations.
Contractors will no longer be able to take short cuts, or go to their local builders merchant to collect a bundle of galvanised beads whether or not they are ‘approved’ for external use. Now we know that they are not.
Of the three options, PVCu beads are already the most popular choice on cost as well as performance grounds. There are no hollow voids to encourage frost damage as they are designed differently from metal beads to ensure that render forms a solid 15mm thick mass at the corner. Additionally, when a through-coloured render is scraped back, the arris is not prominent, nor is it exposed as an unsightly silver line, as with a stainless bead.