Galvanized Hanger Strap vs. Copper Hanger Strapping: Choosing the Right Option for Your Project

When selecting materials for supporting and securing pipes, ducts, conduits, and other components in construction and industrial settings, two of the most common choices are galvanized hanger straps and copper hanger strapping. There are key differences between these two metal strapping solutions that make each better suited for certain applications.

In this comprehensive guide, we’ll compare galvanized steel hanger straps and copper hanger strapping on factors including:

• Material composition
• Strength and durability
• Corrosion resistance
• Conductivity
• Cost
• Appearance
• Suitable applications

Read on to learn the pros and cons of each hanger support system to determine the right one for your specific needs.

Composition of Galvanized Hanger Straps vs. Copper Hanger Strapping

The base metals used in galvanized pipe hanging hardware and copper pipe hanging hardware are quite different:

Galvanized Steel Hanger Straps

Galvanized hanger straps start with an underlying base of steel. This steel is then hot-dipped into a molten zinc bath in a process called galvanization.

The zinc coating applied during galvanization bonds to the steel surface to provide temporary corrosion protection. Galvanized coatings are typically 0.2 to 2 mm thick.

The resulting galvanized steel offers a reasonably strong and rigid durable hanger material for securely supporting moderate loads. The galvanization gives initial rust prevention as well.

Copper Hanger Strapping

Copper hanger strapping begins with strapping made purely from copper metal. Copper has inherent corrosion resistance, so does not require any additional protective coating.

Copper has been used for many decades thanks to its high thermal and electrical conductivity, ductility, and visually appealing appearance. Although not as strong as steel, copper still provides reasonable load support capabilities.

Pure copper is somewhat soft, so copper alloys containing nickel, manganese, aluminum or silicon are also used to increase the base metal’s strength.

Comparing Corrosion Resistance

One of the biggest considerations when selecting a hanger support system is its ability to withstand corrosion long-term:

Galvanized Steel Hanger Straps Resist Corrosion Temporarily

The zinc coating applied during galvanization helps protect the underlying steel from corrosion initially. However, galvanization has some limitations:

• The zinc coating wears away over time when exposed to weather, condensation, salt spray, or abrasion. As it wears thin, the steel becomes more prone to corrosion.
• Imperfections or scratches in the coating expose the raw steel underneath. Since zinc corrodes more readily than steel, these scratches enlarge progressively.
• In damp environments, white rust can form under the zinc coating which reduces its protective abilities.

So while galvanization is helpful at first, it eventually requires replacement, touch-up, or supplemental rustproofing to remain effective.

Copper Hanger Strapping Offers Lasting Corrosion Resistance

On the other hand, copper has inherent, natural corrosion resistance:

• When exposed to air and water, copper oxidizes to form an adherent patina film on the surface. This patina protects against further corrosion of the underlying metal.
• The patina renews itself if damaged, providing ongoing corrosion protection. This allows copper strapping to last for decades.
• Small gaps and imperfections don’t lead to increased corrosion like galvanized coatings. The patina seals these vulnerabilities.
• Copper is more noble than other metals, meaning it has a naturally slower corrosion rate.

In summary, copper offers more complete, longer-lasting corrosion resistance without any additional coatings or treatments.

Comparing Strength and Durability

Hanger systems must be able to securely support associated piping, ductwork, conduit, and other suspended loads without failing. Having sufficient strength for the intended application is critical.

Galvanized Steel Hanger Straps Offer High Strength

Galvanized steel hangers provide impressive strength thanks to the properties of the underlying steel:

• Steel has a high tensile strength, allowing it to support heavy loads without excessive stretching or deformation. This makes it suitable for large ducting, water pipes, etc.
• The notable ductility of steel enables it to flex as needed without cracking. This is especially advantageous where vibration is present.
• Steel maintains its formidable strength even at high operating temperatures. This makes it suitable around hot pipes or in unconditioned spaces.

Galvanized steel is readily available in multiple thicknesses from 18 gauge up to 3/8” plate to handle a wide variety of load capacities. Just ensure the protective galvanized coating remains intact for optimal performance.

Copper Hanger Strapping Has Moderate Strength

Although not as strong as steel pound-for-pound, copper still provides acceptably robust strength for many applications:

• Copper possesses a yield strength capable of safely supporting typical suspended loads. But overloading can cause permanent stretching.
• Certain copper alloys with additions of manganese, nickel, silicon or bronze approach the strength of mild steel when properly cold worked and heat treated.
• Annealing and cold working copper during manufacturing allows optimizing the balance of strength and ductility needed.
• Using thicker copper strapping increases load capacity through a greater cross-sectional area.

So while not exceeding the strength of steel, properly selected copper alloys make durable, rigid hanger strapping systems to meet strength requirements.

Considering Thermal and Electrical Conductivity

In some specialized applications, the need for materials with high thermal or electrical conductivity is important.

Galvanized Steel Hanger Straps Have Minimal Conductivity

Galvanized steel is not the most conductive metal available:

• It has low thermal conductivity, increasing susceptibility to problematic condensation and making it unsuitable near extreme heat sources.
• Galvanized steel also has poor electrical conductivity. This precludes its use for electrical grounding or other applications needing conduction.

Copper Hanger Strapping Boasts Excellent Conductivity

Copper, on the other hand, is one of the most thermally and electrically conductive metals commercially available:

• It has very high thermal conductivity, allowing it to rapidly dissipate heat. This makes it well-suited for heat sinks and HVAC system components.
• Its electrical conductivity is second only to silver. This high conductivity permits uses for electrical wiring, grounding straps, and other conductive applications.

So where thermal or electrical conductivity are important considerations, copper is an excellent choice while galvanized steel may fall short.

Cost Comparison

Another key factor when selecting between galvanized or copper systems is the cost difference:

Galvanized Steel Hanger Straps Are More Affordable

Galvanized steel hangers represent the most cost-effective material option:

• Steel is intrinsically less expensive than copper based on raw material pricing.
• The galvanization corrosion prevention method is inexpensive compared to the inherent resistance of copper.
• Widespread use of galvanized steel in manufacturing keeps overall costs down.
• Galvanized steel parts are readily available at most hardware outlets and building supply retailers.

Copper Hanger Strapping Carries a Cost Premium

Being less common than steel, copper strapping comes at a higher price:

• Copper costs significantly more per pound than an equivalent weight of mild steel.
• Alloying copper with other elements to improve strength further increases cost over pure copper.
• There is greater labor involved in working with copper to fabricate custom strapping and hangers.
• Copper strapping may need to be special ordered through metal suppliers or directly from manufacturers.

The long-term durability and maintenance savings of copper can potentially offset some of these upfront cost premiums. But the initial pricing is undoubtedly higher.

Comparing Appearance

While not as important as structural performance, aesthetic appearance may matter for some visible applications:

Galvanized Steel Hanger Straps Have an Industrial Look

Galvanized steel commonly has a matte gray metallic appearance resulting from its zinc coating. This lends an industrial, utilitarian look.

Some may find it lacking in visual appeal for decorative applications. But its straightforward, workmanlike appearance fits well for purely functional installations.

Copper Hanger Strapping Develops a Unique, Artistic Patina

The warm, reddish-brown color of new copper holds visual appeal for many. As copper ages and patinates, distinctive blue-green areas develop on its surface through natural oxidation.

This patina creates visual depth and interest. The evolving colors and textures can allow copper strapping to serve as an artistic design element in decorative settings.

So where visual appearance is important, copper offers more aesthetic potential compared to galvanized steel.

Applications Best Suited for Each Material

Now that we’ve done a thorough comparison, we can recommend ideal applications for each material based on their specific advantages:

Galvanized Steel Hanger Straps for General Support Uses

With its combination of high strength, initial corrosion resistance, and low cost, galvanized steel works well for:

• Basic residential plumbing and HVAC supports

• Industrial piping and conduit runs where appearance doesn’t matter
• Ductwork above suspended ceilings or in unfinished areas
• General-duty applications without special conductivity or corrosion needs

Just be sure to factor in the decreased lifespan and potential for eventual corrosion and replacement.

Copper Hanger Strapping Where Longevity and Conductivity Are Needed

Copper hanger strapping really excels in applications like:

• Plumbing in chlorinated or saltwater pools where corrosion resistance is critical
• Supporting copper fluid pipes where material compatibility matters
• Decorative exposed piping and hanger systems on display
• Roofing and gutter systems exposed to outdoor weathering
• Conduit providing equipment grounding paths in electrical systems
• HVAC components where condensation resistance is needed
• High-temperature steam lines or heat exchangers

The upfront investment in copper pays dividends through exceptional longevity and reliability.

Conclusion

To summarize, galvanized steel and copper both make viable hanger strap and strapping materials, but each has advantages suiting it better for certain applications. Consider factors like cost, strength, corrosion resistance, conductivity, and appearance when selecting between them.

For cost-effective general hanging duties, galvanized steel provides reliable short-term corrosion resistance. But where the highest levels of corrosion protection, conductivity, and longevity are demanded, copper’s superior properties justify the initial price premium in the long run.

By understanding these key tradeoffs, you can make an informed choice between galvanized hanger straps vs. copper hanger strapping to maximize performance for your specific project requirements.

FAQs

Can copper hanger strapping withstand outdoor exposure?

Yes, copper develops a protective patina when exposed to weather that actually enhances its corrosion resistance. It performs well in outdoor applications.

Do copper hanger systems require special tools?

Copper is soft enough to be worked with standard metalworking tools. But specialized copper alloy straps may require stronger dedicated tooling.

What thickness of galvanized hanger strap is typically used?

For heavy pipes, 3/16” to 1/4” straps are common. Lighter 1/8” straps can be used for conduits and other lighter applications.

Does copper hanger strapping have size limitations?

Yes, copper is difficult to find in very large dimensions. Steel strapping is available in wider/thicker sizes for large pipe runs.

What causes white rust on galvanized steel?

White rust (zinc oxide) forms when galvanizing is exposed to moisture. It signals eventual corrosion of the underlying steel.