The British standard BS 8208-1:1985 Guide to assessment of suitability of external cavity walls for filling with thermal insulants. Existing traditional cavity construction . Is a verbose title but describes exactly what you would expect it to do. When BBA certificates were issued for cavity wall insulation products during the late 80s and 90s they would reference conformity to this standard as evidence that a product and installation of said product conformed to building regulations. The standard was withdrawn on 2009 but products approved approved to this standard by the BBA continued to be installed with reference to this standard for many years after. Anyone working in the industry should have been very familiar with this guidance. For the Cosytherm product in my walls, it is quite explicit: Cosytherm whitewhool Agrément certificate Clearly if CIGA or a surveyor check for conformity to 'industry standard' they would have to take into account this standard as