Galvanising Weight Calculator

Work out galvanising weight instantly with clear inputs, formula shown and shareable results.

About Galvanising Weight Calculator

Zinc has a density of 7.14 g/cm³, so a coating one micron thick weighs 7.14 grams per square metre. Multiplying by area gives the zinc actually deposited, and a wastage allowance covers dross, ash and drainage losses in the kettle. An 85 micron coating, about 610 g/m², is the common requirement for structural steelwork.

Formulas

Coating mass

g/m² = thickness µm x 7.14

Zinc consumption

kg = g/m² x area / 1000 x (1 + wastage)

Worked example

With the default values below, Galvanising Weight Calculator returns Zinc consumption of 34.90. Change any input above and every figure here is recalculated in your browser.

Inputs used

Surface area to galvaniseminimum 0.1 m²: 50 m²
Coating thicknessminimum 1 µm: 85 µm
Zinc wastage allowanceaccepts 0–60 %: 15 %

Results

Zinc consumption: 34.90 kg
Coating mass: 607 g/m²
Zinc deposited on the work: 30.35 kg
Coating thickness in mils: 3.35 mil

Step by step

1Values used
2Coating mass
3Zinc consumption
4Zinc consumption= 34.90 kg
5Coating mass= 607 g/m²
6Zinc deposited on the work= 30.35 kg
7Coating thickness in mils= 3.35 mil

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is the Galvanising Weight figure worked out?

g/m² = thickness µm x 7.14. Zinc has a density of 7.14 g/cm³, so a coating one micron thick weighs 7.14 grams per square metre.

Does thicker galvanising last proportionally longer?

Yes, close to it. Zinc corrodes at a broadly steady rate for a given atmosphere, so life to first maintenance scales almost linearly with coating thickness.

What values do I need to enter?

This calculator takes 3 inputs: Surface area to galvanise, Coating thickness, Zinc wastage allowance. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.