In April, the ISO 11 600 performance-based international standard for sealants will come into force in the United Kingdom. The standard is designed to simplify the task of architects, builders and gla…
In April, the ISO 11 600 performance-based international standard for sealants will come into force in the United Kingdom. The standard is designed to simplify the task of architects, builders and glazing engineers when seeking the right product to seal a window, for example. ISO 11 600, which will apply across Europe now that the United Kingdom has adopted it, allows sealants to be specified on a range of criteria, including movement capability, how easily a material returns to its original shape and how hard a seal it provides. ISO 11 600 covers 11 sealant categories: four of these describe glazing sealants, the other seven describe facade sealants. Each sealant has its own coded designation comprising a series of numbers and letters, for example, ISO 11 600-G-20HM. The first letter in the definition following the standard number (ISO 11 600) refers to the end use. Glazing sealants are designated by the letter G, facade sealants by the letter F. After the end-use letter comes a number based on the sealant“s movement capability. The standard then indicates two classes for hardness: high modulus (HM) for hard products and low modulus (LM) for soft sealants. A sealant“s designation is based on tests involving three standard substrates: mortar, glass and anodised aluminium. The substrate used is also included in the designation, together with any primers or surface conditioners used in the testing. If the substrate is not representative of the actual materials used, a specifier can then ask for additional tests. With the basic properties of the sealant specified, other requirements of the application will need to be included, such as life expectancy, colour, adhesion, non-staining, and resistance to fire, water, chemicals and abrasion.