The application of a protective zinc coating to steel or iron in order to stop corrosion is known as Galvanization or Galvanising. The most popular technique involves immersing the components in a bath of hot, molten zinc.
When the zinc coating is intact, corrosive chemicals cannot penetrate to the steel beneath. Galvanized steel has a long lifespan.
Galvanized steel doors are often made of polystyrene/polyurethane cores that are wrapped in steel with rock wool or honeycomb in a special technique to maximise insulation and built with thermal adhesives to increase structural integrity.















