Galvanised Steel vs Stainless Steel: Which is the Better Metal?

Galvanised steel and stainless steel both have reputations for being exceptionally strong and durable metals, but which one is the best? There’s no straightforward or objective answer to this question; a metal’s performance level depends on a lot of different factors, including what it will be used for and the environment in which it will be installed. In this post, we’ll take a look at the qualities of both metals, so you can decide which one is best for your project.

The Neuer Zollhof building in Dusseldorf, designed by Frank O. Gehry, is clad in gleaming stainless steel. Photo by Di on Unsplash

How they two types of steel are made

Galvanised steel is coated in a layer of zinc, which helps to protect it from oxidisation (rusting). Stainless steel, on the other hand, is an alloy, which means it is a mix of more than one type of metals. In this case, chromium is added to the steel when it is in its molten state. All stainless steel contains at least 10.5% chromium, but it can be up to 20%. As the chromium is actually mixed in with the steel, rather than just coating it like the zinc on galvanised steel, it is the stronger of the two metals.

Stainless steel and galvanised steel vs. the elements

Both stainless steel and galvanised steel are exceptionally resistant to the elements, which is why they’re used a lot in the great outdoors. As we explained above, however, stainless steel contains the strengthening ingredient of chromium, whereas galvanised steel simply has an outer layer of protective zinc. With this in mind, stainless steel is more resistant to rain, and therefore rust, than galvanised steel. The rust-resistant properties of galvanised steel should not be overlooked, though: in the right environment, galvanised steel can last for decades, which is why it’s so popular in garden design. Galvanised steel does oxidise more quickly when it is exposed to saltwater, though, so it won’t last quite as long if installed very close to the coast.

Our galvanised steel garden edging.

 

 

 

 

 

 

 

 

 

 

 

Which is stronger?

Again, owing to the way it is made with the addition of chromium, stainless steel is stronger and more durable than galvanised steel. That said, galvanised steel is still a very strong and durable metal.

Appearance

Galvanised steel and stainless steel are both silver-grey in colour, but each has their own unique aesthetic, making them easy to tell apart. Most of us are familiar with stainless steel in the kitchen: sinks, taps and cutlery are all often made from stainless steel. Thanks to that added chromium, well-maintained stainless steel possesses a polished, shiny finish. Galvanised steel, on the other hand, tends to have a duller finish, often with a mottled pattern on its surface.

Cost

Given the fact stainless steel is more resilient and longer-lasting than galvanised steel, it should come as no surprise that it is the more expensive of the two metals. As a general guide, stainless steel usually costs three to four times the price of galvanised steel.

Summary

Both stainless and galvanised steels are strong materials capable of withstanding the elements for a considerable amount of time. Out of both metals, stainless steel is the strongest and most resistant to corrosion, but because of these properties, it is also the most expensive. If you’re looking for a more budget-friendly metal that will last in most outdoor settings for a decade or more, you’ll get the results you want with a lower price tag from galvanised steel.