Why Galvanized Steel Is So Popular in Modern Construction

Whether you’re constructing a new home, office building, warehouse or other type of structure, steel will likely play a major role. It is incredibly strong and able to withstand extreme amounts of stress. 

However, steel still has one major drawback – it rusts.

If steel is left exposed to moisture and oxygen for extended periods of time, rust begins to develop. In construction and industrial settings, rust weakens materials, increases maintenance costs and shortens the life expectancy of structures and equipment. 

That's why galvanized steel has gained such popularity throughout the world in modern construction. 

By applying a protective layer of zinc to steel using a galvanization process, manufacturers are able to add corrosion resistance to steel and ultimately extend the life of steel-based metal components.

What Is Galvanizing and Galvanized Steel?

Galvanizing refers to the act of applying a protective layer of zinc to steel or iron to reduce corrosion and rust. 

Most galvanizing processes utilize what is referred to as "hot-dipped" galvanizing. Hot-dipping involves submerging the steel product into a vat filled with liquid zinc. 

Once the steel has cooled sufficiently, the zinc coating has bonded itself to the steel. This resulting bond is extremely durable and protects the underlying steel from being compromised due to corrosion.

As the zinc coating degrades over time due to weather exposure, etc., it will begin to corrode prior to the degradation of the steel beneath it.

Appearance Of Galvanized Steel

Galvanized steel typically appears as a light grey/silver color.

Additionally, some galvanized coatings have a distinctive crystalline texture (like frost), known as “spangles”, that appear after cooling during the galvanizing process.

A shiny metallic appearance is typical of new galvanized coatings. Older galvanized coatings tend to appear duller over time.

Both the type of galvanizing used and the thickness of the applied zinc coat affect how a galvanized surface appears.

Does Galvanized Steel Rust?

Galvanized steel contains high levels of rust-resistance however it is not completely impervious to rust for eternity.

Eventually, the external zinc coating will deteriorate at varying rates based on environmental conditions. However, compared to uncoated steel, galvanized steel will experience considerably less corrosive damage before exhibiting significant signs of deterioration.

Typically, galvanized steel can function for decades without needing extensive repairs or maintenance, although environmental conditions can affect longevity.

Advantages of Galvanized Steel

Corrosion Resistance

The zinc coat prevents moisture and oxygen from coming into contact with the steel beneath, thereby increasing the longevity of the metal in both indoor and outdoor settings.

According to data provided by the American Galvanizers Association (AGA), galvanized steel will corrode approximately 1/30 as fast as uncoated steel under similar environmental conditions.

Due to its corrosion resistance properties, galvanized steel can perform for decades without requiring much maintenance.

Extended Service Life

Galvanized steel is known for its extended service life. 

While some types of galvanized coatings may fail prematurely due to environmental factors or improper handling, many applications utilizing galvanized coatings can function reliably for decades with limited maintenance.

Low Maintenance Requirements

Another benefit of using galvanized steel is its minimal maintenance needs. Since the zinc coating provides continued protection for the underlying steel for a prolonged period, galvanized steel can be used in demanding outdoor environments for decades before costly repair work becomes necessary.

Affordable Protective Options

While more expensive than other corrosion-resistant metals such as stainless steel, galvanized steel is a less expensive alternative offering comparable levels of durability.

For many project specifications, galvanized steel provides a suitable trade-off between performance, lifespan, and cost.

Strength & Versatility

Unlike many corrosion-resistant materials that compromise on strength and versatility, galvanized steel maintains the strength of standard carbon steel while providing added corrosion-resistance protection.

Therefore, galvanized steel can be utilized effectively in multiple construction-related projects, including those in industrial facilities and manufacturing environments.

Methods of galvanizing

Hot-dip galvanizing

Hot dip galvanizing is the most commonly employed technique.

Hot dip galvanizing involves immersing steel into molten zinc to produce a high-quality, durable coating that can withstand extensive corrosion.

The process is primarily used for structural frame members of buildings, bridges, fencing materials, utility structures, etc., due to their durability and anti-corrosive properties.

Galvannealed Steel

Galvannealing combines hot dip galvanizing with post-heating treatment processes. Post-heating treatments enable the formation of matte finishes on galvannealed steels. These finishes are easily painted and welded. 

Therefore, this technique is generally used in applications requiring a uniform finish such as car bodies, appliances, tools and machinery components.

Pre-Galvanized Steel

Pre-galvanized steel refers to a process in which a zinc-coat is applied onto steels prior to their final processing stages (i.e. cutting/welding). 

Pre-galvanized techniques are mainly employed for producing sheet metals, tubes/pipes/fittings, wire mesh fences, and large quantities of processed flat products such as corrugated sheets etc.

Electro-galvanizing

Electro-galvanizing employs an electrochemical process to deposit a thin layer of zinc onto a substrate (the base metal). 

Due to its smoothness and thinness compared to hot-dip galvanized steels this technique finds widespread application in automotive industry and in manufacturing areas where cosmetic appeal takes precedence over mechanical integrity.

Conclusion

Galvanized steel has earned a reputation as one of the top-rated building materials in contemporary construction due to its inherent ability to combine strength and durability in addition to providing a durable long-lasting material that can withstand prolonged exposure to harsh environmental factors. 

Furthermore, due to its low-maintenance requirements and affordability relative to alternative corrosion-resistant products, galvanized steel has gained widespread acceptance among a wide range of industries.