Fence glossary · Materials
Galvanized
Steel coated in zinc so the zinc corrodes first and protects the steel underneath. In fencing it describes chain link fabric, framework and fittings, and it is why a bare chain link fence in this climate greys rather than rusts through. Coating weight, not the word itself, decides how long it lasts.
Zinc protects two ways. It is a physical barrier, and it is sacrificial — where the coating is scratched, the surrounding zinc corrodes preferentially and shields the exposed steel instead of leaving it to rust. That is why a galvanized fence tolerates the knocks a chain link fence actually takes in service, and why a painted steel fence with the same scratch starts a rust spot that spreads under the film.
Two distinctions matter when specifying. Hot-dip galvanizing immerses the steel in molten zinc and lays down a much heavier coating than the electro-galvanized process used on light commodity goods. And on chain link fabric, galvanized-after-weaving coats the knuckles and the cut wire ends that galvanized-before-weaving leaves bare — which is exactly where a fence starts to bleed rust first. The pipe framework carries its own coating spec, inside and out, and interior coating is what keeps a post from rusting from the water that sits in it.
The fittings decide the outcome as often as the fabric does. Tension bands, brace bands, rail ends, caps and the tension wire itself are the small steel parts that go first, particularly on a retention basin enclosure standing in saturated ground for weeks at a time. Matching the fittings to the framework rather than accepting whatever is in the bin is the cheap decision that keeps a chain link fence looking maintained a decade in.
