Choosing the Right Strapping Material for Your Packaging Needs

Strapping is used to bundle products, reinforce packages, and unitize palletized loads for handling, storage, and transportation. Choosing the right strapping material depends on what you are securing, how much tension is required, how the load behaves during transit, the environment it will encounter, and the tools or equipment used to apply the strap.

Three of the most common industrial strapping materials are polypropylene, polyester, and steel. Each has different strength, elongation, tension-retention, handling, and application characteristics.

For the complete selection process—including strap material, break strength, elongation, tension retention, joint method, tools and equipment—start with our Strapping Selection Guide.

Why Strapping Material Matters

The strongest strap is not automatically the best strap. Effective strapping needs to match the load and maintain the required tension without damaging the product or packaging.

When selecting strapping, consider:

• Load weight and rigidity.
• Whether the load settles, compresses, expands, or shifts.
• Required break strength and applied tension.
• Sharp or abrasive edges.
• Indoor, outdoor, moisture, and temperature exposure.
• Manual, battery-powered, semi-automatic, or automatic application.
• Operator safety and handling requirements.
• Total material, equipment, and labor cost.

1. Polypropylene Strapping

Common fit: Light- to medium-duty bundling, carton closing, and unitizing applications.

Polypropylene, or PP, strapping is lightweight, flexible, and widely used for general packaging applications. It has relatively high elongation, allowing it to stretch as tension is applied.

Advantages

• Lightweight and easy to handle.
• Available for manual and equipment-based applications.
• Useful for cartons, bundles, and many lighter palletized loads.
• High elongation can accommodate some movement or compression.
• Often an economical option for general-purpose strapping.

Considerations

• Generally provides lower break strength and retained tension than comparable polyester strapping.
• May not be appropriate for heavier, rigid, or highly demanding loads.
• Outdoor and UV exposure should be evaluated against the specifications of the particular strap.
• Sharp product edges may require edge protection or a different strapping solution.

Common applications: Cartons, printed materials, light bundles, totes, and lighter pallet loads.

2. Polyester Strapping

Common fit: Medium- to heavy-duty palletizing and unitizing applications where strength and retained tension are important.

Polyester, or PET, strapping provides higher break strength and generally retains more applied tension than polypropylene. Its elongation and recovery characteristics can also help it accommodate shock and loads that settle or change slightly during transportation. Polyester is commonly used as an alternative to steel in applications where its performance characteristics meet the load requirements.

Advantages

• Higher break strength than typical polypropylene strapping.
• Good retained tension for palletized and unitized loads.
• Elongation and recovery can help absorb shock.
• Lighter and generally easier to handle than steel.
• Available for manual, battery-powered, and automated strapping systems.

Considerations

• Typically costs more than general-purpose polypropylene strapping.
• Tools, seals, buckles, or weld systems must be compatible with the specific strap.
• Not every polyester strap has the same strength, UV resistance, or weather performance.
• Very sharp or abrasive loads may require edge protection or another strapping construction.

Common applications: Palletized products, lumber, building materials, bottles and containers, corrugated loads, and other medium- to heavy-duty unitizing applications.

3. Steel Strapping

Common fit: Very heavy, rigid, non-compressible, sharp-edged, or demanding industrial loads.

Steel strapping provides high strength with relatively low elongation. That makes it useful where the load requires strong, rigid securement and where significant stretch in the strap is undesirable.

Advantages

• Available in high-strength constructions for demanding industrial loads.
• Low elongation compared with plastic strapping.
• Useful for rigid loads and applications where minimal strap stretch is required.
• Available in different finishes and grades for specific environments and applications.

Considerations

• Heavier than plastic strapping and requires appropriate handling procedures.
• Cut ends and released tension can create injury hazards if the strap is handled improperly.
• Corrosion resistance depends on the finish, coating, storage, and environment.
• Tools and equipment must be designed for the specific steel strap being applied.

Common applications: Metal products, coils, pipe, heavy building materials, machinery, and other rigid industrial loads.

Safety note: Follow the strapping manufacturer's instructions and your workplace safety procedures when tensioning, sealing, cutting, or removing steel strapping. Use the appropriate personal protective equipment and tools for the application.

Polypropylene vs. Polyester vs. Steel Strapping

How to Choose the Right Strapping Material

Start with the load rather than selecting strapping by price or material name. Two loads with the same total weight may require very different strapping if one is rigid and uniform while the other settles, shifts, or has sharp edges.

1. Determine What the Strap Needs to Do

Are you closing cartons, bundling products, reinforcing packages, unitizing a pallet, or restraining a heavy industrial load? The required strength and tension can differ substantially between these applications.

2. Consider Load Behavior

Loads that settle, compress, expand, or experience shock during transportation require strapping that can maintain useful tension as the load changes. Polyester is often selected for this reason because of its elongation and recovery characteristics.

3. Check Break Strength and Applied Tension

Strap width, thickness, grade, and construction affect break strength. Do not assume that every polypropylene, polyester, or steel strap provides the same performance. Compare the specifications of the actual product being considered.

4. Evaluate Edges and Pressure Points

Sharp or vulnerable load edges can damage strapping or be damaged by concentrated strap pressure. Edge protectors can distribute pressure and help protect both the strap and the packaged product.

5. Consider the Environment

Outdoor storage, moisture, temperature variation, sunlight, corrosive environments, and long shipping cycles can affect strap selection. Verify the environmental specifications of the actual strapping rather than assuming every strap of a particular resin or material behaves the same way.

6. Match the Strap to the Tool or Machine

Strap material, width, thickness, surface, joint method, and coil specifications need to be compatible with the tensioner, sealer, buckle, friction-weld tool, or strapping machine being used.

The Role of Strapping Tools and Equipment

The strapping material is only one part of the system. Application method affects tension, joint strength, consistency, speed, and operator effort.

• Manual tools: Useful for lower-volume, mobile, or occasional applications.
• Battery-powered tools: Can combine tensioning, sealing, and cutting while reducing manual effort for compatible plastic strapping.
• Pneumatic tools: Used in some industrial applications where compressed air is available.
• Semi-automatic and automatic equipment: Useful where repeatability and higher throughput are priorities.

Use tools, seals, buckles, and equipment specifically approved for the strap material and dimensions being applied.

Strapping as Part of a Load-Securement System

Strapping does not operate independently from the rest of the package. Pallet pattern, carton strength, stretch film, edge protection, load geometry, weight distribution, and handling conditions can all affect the secured load.

For a broader look at these components, see our Palletizing & Load Securement Supplies resource and Palletizing Best Practices guide.

The Bottom Line

Choosing between polypropylene, polyester, and steel strapping requires more than comparing which material is strongest. Polypropylene works well for many lighter general-purpose applications. Polyester provides higher strength and retained tension for many medium- and heavy-duty loads. Steel remains useful for demanding applications requiring high strength with relatively low elongation.

The right choice depends on the load, required tension, product sensitivity, environment, handling process, application equipment, and total cost of the strapping system.

Need Help Choosing Strapping?

Browse our strapping supplies to compare polypropylene, polyester, steel strapping, tools, seals, buckles, and related accessories.

If you're evaluating strapping for a palletized load, bundling application, or industrial packaging process, Contact Packaging HERO to discuss your application.

Frequently Asked Questions