Galvanised mesh panels are renowned for their superior weathering and structural qualities and are fit for a number of building applications.
In Geelong we see it commonly used in fencing projects, screening, cage trailers and animal enclosures. Around the world it’s used in even more interesting projects. Here’s a home in Japan with an enclosed balcony on top of a garage!
What is ‘Galvanisation’ anyway?
Galvanisation is a corrosion protection system. Steel is prone to rusting quickly because it reacts with oxygen in the atmosphere which acts to break down the steel. Zinc doesn’t react in the same way, the atmosphere actually hardens it and protects the layer of steel beneath. Another interesting point is that because of a difference in the electromagnetic properties of steel and zinc, zinc can continue to protect exposed steel even when the zinc layer has been slightly damaged. This of course will depend on how damaged the area is.
Hot-dipped Galvanised Mesh
Galvanised Mesh is so durable because of the hot-dip galvanisation process. This is where a coating of zinc is applied over the steel by immersing it in a bath of molten zinc.
You would have noticed that when galvanised mesh is new it’s shiny but then over time it changes to a dull grey colour. This is a form of corrosion on the surface that actually protects from further corrosion.
When exposed to the atmosphere, pure zinc reacts with oxygen to form zinc oxide, this is the shiny stage. That surface then further reacts with carbon dioxide forming zinc carbonate. This is the dull grey colour.
Welding Galvanised Mesh
Galvanized steel can be welded however it’s important to exercise caution by way of an appropriate breathing apparatus and good ventilation as zinc fumes are highly toxic. You also need to watch the temperature as taking galvanised mesh or any galvanised steel above 200 degrees will result in peeling of the zinc at the layer that the zinc meets the steel. This will ruin the protection in that area.