what is the difference between galvanised iron and zincalume?
A. Galvanised steel is coated in almost pure zinc while ZINCALUME® steel is coated in an alloy of approximately 55% aluminium, 43.5% zinc and 1.5% silicon. ... This sacrificial mechanism is similar to galvanised steel in the typical (thinner) product thicknesses used in roofing and walling applications.