How to Specify Bespoke Polythene Film: Width, Thickness and Quantity Explained

Ordering bespoke polythene film can seem complicated, particularly if you are replacing an existing product without a technical specification.

A packaging supplier may ask about film width, thickness, material, reel size and annual usage. However, you do not need to know every answer before requesting advice.

At Stretchband Packaging, we help UK businesses identify the right film specification for their product, machinery and packing process. Here are the main details that help us recommend and quote the most suitable solution.

1. What are you packaging?

The best starting point is the application. Tell your supplier what is being wrapped, bagged, bundled or protected. Useful details include:

• The product’s dimensions and weight

• Whether it has sharp edges or corners

• Whether the packaging will be used manually or automatically

• The level of protection required

• Whether the film needs to shrink, stretch or heat-seal

• Storage and transport conditions

A film suitable for lightweight e-commerce products may be very different from one used for engineering components, food products or heavy industrial items.

2. Which polythene format do you need?

Polythene packaging is available in several formats, including:

• Single-wound sheeting

• Lay-flat tubing

• Pre-made bags and sacks

• Collation shrink film

• Stretch banding film

• Printed packaging film

• Bespoke liners

If you are unsure, describe your packing process and equipment. We can then recommend the most appropriate format from our range of polythene packaging films.

3. Film width

Width is normally measured across the open film.

For lay-flat tubing, the quoted width is usually the flat width of the tube—not its full circumference. For single-wound film, it is the width across the sheet.

The correct width should provide sufficient coverage without using unnecessary material. If you have an existing reel, measure it across the face or send us a photograph of its label.

4. Film thickness or micron

Polythene film thickness is normally expressed in microns, written as μm.

A higher micron does not automatically mean a better film. The correct thickness depends on the material blend, product weight, puncture risk and machinery.

Over-specifying film increases material consumption and cost. Under-specifying it may cause splitting, punctures, weak seals or production stoppages.

Where appropriate, we can assess whether a more efficient specification could maintain performance while reducing material usage.

5. Reel and core requirements

For machine-fed film, reel construction can be just as important as the film itself. Useful information includes:

• Maximum reel diameter

• Maximum reel weight

• Cardboard core internal diameter

• Winding direction

• Number of reels required

• Machine manufacturer and model

These details help ensure that the finished reels fit your equipment and unwind consistently.

6. Virgin, recycled or specialist material

Depending on the application, options may include:

• Virgin LDPE

• Recycled or PCR-content film

• Food-contact grades

• Coloured or opaque film

• Anti-static film

• UV-stabilised film

• VCI corrosion-protection film

• Non-fusion material

Businesses considering recycled content should review the current HMRC Plastic Packaging Tax guidance. Packaging containing less than 30% recycled plastic may be subject to the tax, depending on the organisation’s circumstances. HMRC guidance should be treated as the authoritative source.

Stretchband Packaging can discuss suitable recycled and PCR polythene options for your application.

7. Printing requirements

Polythene film can be printed with branding, instructions, warnings, recycling information or product identification.

When requesting printed polythene film, consider:

• Number of print colours

• Print coverage

• Repeat length

• Film colour

• Whether the film runs through sealing equipment

• Required artwork format

The film construction and surface treatment must be compatible with both the printing process and the packaging machinery.

8. Quantity and delivery requirements

Your expected order quantity or annual usage helps determine the most efficient manufacturing route.

If you do not know the exact volume, an estimate is sufficient. Tell us how many reels, bags or kilograms you currently use each month or year.

It is also useful to provide the delivery postcode and any stockholding or scheduled-delivery requirements.

What if you do not have a specification?

That is not a problem. You can provide:

• A sample of your existing film

• A photograph of the reel label

• Product dimensions

• Machine details

• A description of the current problem

• Your approximate usage

Our team can use this information to help identify a suitable starting specification.

Speak to a packaging film expert

Whether you need a replacement film, a new bespoke solution or help improving an existing specification, Stretchband Packaging can recommend the appropriate material and reel format.

Send us your packaging requirements for technical guidance, samples or a quotation.

Bespoke polythene film specification support

If you are unsure about any part of your specification, our team can help review samples, reel labels, machinery details and usage requirements.