Stretch film—often called pallet wrap—is a mainstay of modern warehousing and logistics. It holds pallets together, helps prevent product damage, and streamlines the shipping process.
Yet one element that frequently goes unnoticed is the core around which the film is wound. Understanding variations in core size and weight can improve load stability, reduce handling issues, and even boost your sustainability profile.
In this article, we’ll explore what the core in stretch film is, how its dimensions and weight can affect outcomes, and how to choose the right options for your business.

Introduction
Stretch film may seem straightforward—pull, wrap, and stabilise. However, if you’ve encountered problems like excessive film consumption, pallets toppling in transit, or worker strain from lifting heavy rolls, the cause might lie in core differences rather than the film itself. Choosing the right core dimensions is a subtle but important factor for warehouse teams.
One reason core size and weight often go unexamined is that they appear to be small details compared to film stretch or cling. But think about it this way: if you’re swapping out rolls multiple times a shift, dealing with a specific dispenser size, or shipping film across sites, the core’s attributes can make or break operational efficiency.
In the sections that follow, we’ll define the core in stretch film—covering differences in hand films and machine films—and see how core size and weight affect everything from ergonomics to sustainability.
Defining the Core in Stretch Film
In every roll of stretch film, there’s a cylindrical tube—usually cardboard but sometimes plastic—that supports the film and provides a way to mount it onto dispensers or machines. The important measurements include the inner diameter (often 2 or 3 inches) and the length (matching the film width, though extended cores can go beyond that width for manual gripping).
Hand Films: Standard vs. Extended Cores
Standard Core Hand Wrap: Matches the film width, requiring a handheld dispenser for application. The core isn’t necessarily extended beyond the edges of the film.
Extended Core Hand Wrap: Features a core that sticks out beyond the film on one or both sides, allowing users to grip it directly. This can eliminate the need for a separate dispenser and potentially improve ergonomics. However, an extended core adds cardboard weight and bulk.
Machine Films
Machine films come in standard widths (e.g., 500 mm) and typically use a 3-inch inner diameter. That diameter must fit your automatic or semi-automatic stretch-wrapping equipment. A mismatch can lead to downtime, poor wrap tension, and operator frustration. The sturdiness of the core is also crucial: machine operations often run at higher speeds and tension levels, so a flimsy tube can cause film alignment issues.
What Difference Do Core Sizes Make?
Core size usually refers to the inner diameter (ID). The most common sizes in the UK (and globally) are 2 inches (about 50 mm) and 3 inches (about 76 mm). Occasionally, you might see variations (like 2.5 inches), though they’re not as widespread.
Handling and Ergonomics
Smaller Core (e.g., 2-inch):
May be easier to grip for some users.
Could require specialised dispensers.
If the film is thick or the roll is large in diameter, the total weight might still be significant.
Larger Core (3-inch):
The industry standard for machine wraps.
Compatible with most manual dispensers designed for 3-inch IDs.
Allows for larger roll capacity (if outer diameter also increases), potentially reducing roll changeovers.
Efficiency and Roll Changes
A larger inner diameter can accommodate a bigger roll—assuming the outer diameter and film thickness align. This means:
Fewer changeovers for high-throughput operations, saving labour time.
Potential for heavier rolls, which might strain operators if they’re manually lifted.
On the other hand, smaller cores might be beneficial if your operation relies on more frequent, shorter wrap sessions or if staff find large rolls too heavy to handle regularly.
Equipment Compatibility
Most automated wrappers are built with a 3-inch spindle, reflecting the prevalence of that size. If you buy 2-inch core films for a machine set up for 3-inch, you risk mechanical issues or the expense of retrofitting. Always check equipment manuals or consult your supplier before making large orders.

What Difference Does Core Weight Make?
When talking about weight, it’s crucial to distinguish core weight from film weight. The core weight is the mass of the cardboard or plastic tube, while the film weight is the mass of the stretch film itself. Combined, they give the gross roll weight.
Operator Safety and Ergonomics
Heavier cores increase the gross weight, which can lead to:
Fatigue or injury risks for staff who lift numerous rolls each day.
Slower operation if workers struggle to load or unload heavy rolls onto dispensers or machines.
Conversely, a lighter core might ease handling but may be less durable in high-speed machine environments, or it may hold less film overall.
Shipping and Storage Costs
Higher transport costs: Heavier rolls cost more to ship, which can add up if you’re moving them between multiple sites or to customers.
Storage constraints: Rolls with dense cores might limit how high you can stack them or how many you can store in a given space, due to racking weight limits.
Perception vs. Reality
Some buyers believe that a heavier roll equates to more film, but it might simply be a denser or thicker core. Always ask suppliers to clarify the net film weight and length, so you can accurately compare cost and usage between different products.
Sustainability and Environmental Considerations
With rising emphasis on corporate social responsibility, it’s essential to evaluate how your choice of core affects the environment.
5.1 Core Materials
Cardboard: Generally easier to recycle and often made with a percentage of recycled content.
Plastic: May offer durability and reusability but can be harder to recycle depending on local facilities.
Waste Management
Multiple Smaller Cores: If you use lots of smaller rolls and discard them frequently, you’ll accumulate more cores to recycle.
Fewer Larger Cores: Could mean less total core material in the system, though each individual core may be heavier.
Overall Film Usage
Advanced resin technology means you can often choose thinner gauges that maintain adequate load stability. Pairing the right gauge with an appropriate core size can reduce total plastic consumption—and your carbon footprint. Ultimately, wasted film or poorly wrapped pallets can cost you more in damaged goods and reworked shipments, so a balance between film efficiency and core design is key.
Carbon Footprint
Heavier rolls might require more fuel to transport.
Lighter rolls could mean more total shipments if you end up needing more film more often.
Evaluate your operational scale: a high-volume facility might benefit from fewer roll changeovers and thus fewer transport cycles, even if individual rolls are heavier.
Conclusion
Although the core may seem minor next to film thickness or stretch capacity, it can make a substantial difference in cost, ergonomics, and environmental impact. Here’s what to keep in mind:
Core Size:
Smaller cores can offer easier gripping or compatibility with certain dispensers, but they may hold less film.
Larger cores reduce roll changes and are typically standard for machine wraps, but they can be heavier and require greater operator strength.
Core Weight:
Heavier cores add to the overall roll weight, influencing shipping costs and operator safety.
Lighter cores may need more frequent changes or lack the durability needed for high-speed wrapping.
Practical Implications:
Equipment compatibility: Check the spindle size of your stretch-wrapping machines.
Labour and safety: Weigh up the trade-offs between fewer changeovers (heavier rolls) and reduced strain on employees (lighter rolls).
Cost and value: Clarify net film weight versus gross weight to avoid overpaying for extra core material.
Sustainability:
Consider recycling or reusing your cores.
Opt for film gauges that meet load stability requirements without unnecessary plastic.
Balance transport emissions with operational efficiency.
In a fast-paced warehouse, small details can have an outsized effect. By giving due attention to the core—and not just the film wrapped around it—you position your business for smoother operations, healthier employees, and a more sustainable approach to packaging. If you’d like to learn more about how to find the right film, and core sizes, for your operations – then get in touch with our expert team today by visiting the link here.