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Plastic-Free Packaging for Dry Bags

What plastic-free actually means in practice

Plastic-free describes the packaging, not the product. A welded TPU dry bag is a polymer article and will remain one for the foreseeable future, because no fibre alternative currently matches its combination of weldability, abrasion life and flexibility at low temperature. The goal is that nothing additional arrives with it that has to be thrown away in the first thirty seconds of ownership.

The definition needs to be written down before any material is ordered, because the gaps are where problems start. A kraft sleeve with a plastic laminate window is not plastic-free. Gummed paper tape with a polypropylene reinforcing scrim is not plastic-free. A moulded pulp tray treated with a fluorinated oil repellent is not plastic-free in several jurisdictions, and it is also not kerbside recyclable. Write the exclusions into the specification, not into the marketing copy.

Recyclability and compostability are separate claims and should not be mixed. A material is recyclable if it can be collected, sorted and reprocessed in an existing stream, which for paper and board means kerbside collection in most markets. It is compostable only if it breaks down in a defined facility within a defined time, and most compostable films require an industrial plant rather than a home heap. The self-declared claim rules published by the ISO under ISO 14021 are the reference worth naming here.

Where packaging plastic hides on a bag program

Most teams audit the polybag and stop there, and the polybag is the smallest of the five items. Bubble wrap and foam inserts are the real mass, and they exist because of a damage assumption rather than a test result. In our experience of packing waterproof bags, an unfilled roll-top bag is one of the most damage-tolerant products in any warehouse: it has no rigid frame, no glass and no sharp edges, and it absorbs impact by deforming.

That means the protective packaging is largely there to protect the carton, not the bag. Once you recognise that, the substitution becomes simpler: the bag needs scuff protection and the carton needs compression strength, and those are two different problems with two different fibre solutions. A kraft sleeve handles the first; a board grade upgrade handles the second.

Material options: kraft, pulp, board and paper tape

Four materials cover almost every substitution. Kraft paper, either virgin or recycled, is the sleeve and wrap material: cheap, kerbside recyclable and printable, with poor wet strength unless treated. Moulded pulp, made from recovered paper or bagasse, replaces foam for shaped protection and absorbs impact by crushing. Corrugated board in a higher grade replaces the structural role of foam. Gummed paper tape replaces plastic tape and bonds to the carton rather than to itself.

The trade-offs are real and should be stated honestly. Virgin kraft has about 25% more burst strength than recycled kraft at the same basis weight, so a recycled sleeve needs to go from 80 to 90 grams per square metre to match it. Moulded pulp costs around 30% more than bubble wrap per unit and takes more warehouse volume. Gummed tape needs a water dispenser at the packing bench, which is a one-off capital item and a change in workflow rather than a material cost.

There is one material to approach with caution: compostable film. It looks like the easy answer because it behaves like the polybag it replaces, but it costs roughly three and a half times as much, it is not kerbside recyclable, and it only breaks down in an industrial facility. If the destination market has no such facility, you have paid more to create a worse outcome. Use it only where a specific retail account requires it.

Performance testing for fibre packaging

Three tests decide whether a fibre system is viable, and they should be run on loaded cartons rather than empty ones. A drop test from 1 m on all six faces catches corner crush. A vibration test on a standard profile catches the slow abrasion that loosens sleeves. A humidity soak at 40 °C and 90% relative humidity for 48 hours catches the failure that fibre packaging actually suffers: board softening.

The humidity result is the one that surprises people. Corrugated board loses 15% or more of its compression strength when it equilibrates at high humidity, and in a sea container crossing the tropics that is not a hypothetical condition. The response is either a higher board grade, a desiccant in the carton, or a stretch-free outer wrap; the third option is the least attractive because it reintroduces a film.

Moisture and transit risk

The product inside is waterproof, which creates a false sense of security about the packaging around it. A dry bag survives a soaking; the carton it ships in does not, and a carton that arrives soft and split is a write-off regardless of the condition of the bag. Moisture is therefore a packaging problem and not a product one, and it needs to be solved at the carton level.

Three controls work. Specify board with a stated wet-strength or a higher ring crush value, which handles moderate humidity without changing the pack-out. Add a desiccant sachet per carton for long sea legs, typically 5 to 10 grams of silica gel per cubic metre of carton volume. And keep cartons off container floors and away from container walls, where condensation forms, by using a pallet and a breathable top sheet.

Air freight changes the risk profile in the opposite direction. Humidity is lower, handling is faster and stack heights are smaller, so fibre packaging performs better by air than by sea. If your program mixes lanes, it is entirely reasonable to run the full fibre specification for air and a hybrid with a higher board grade for sea, and to say so in the documentation rather than pretending one specification fits every route.

Cost and freight maths

The direct comparison is closer than most people expect. Plastic packaging for a 20L bag costs about 0.14 in material; the fibre equivalent costs about 0.146, a 4% increase. That small delta is the honest number, and it is worth quoting precisely because it is unimpressive: the argument for changing is regulatory and brand-driven, not a cost saving, and pretending otherwise damages credibility when the invoice arrives.

Freight is where fibre costs more. Paper and board are heavier and bulkier than film, so a container that held 9,000 units in polybags may hold 8,400 in kraft sleeves and pulp trays. That is a 7% reduction in units per container, which on a long sea leg is a real increase in landed cost per unit. Two things offset it: the pulp trays can often be nested, and a sleeve takes less volume than the bubble wrap it replaces.

There is also a downstream cost that goes down rather than up. Extended producer responsibility fees in most markets are now modulated by recyclability, so a fibre-only pack moves into a lower fee band. On a program of 20,000 units a year the fee difference frequently exceeds the material difference, which converts the whole change from a cost into a saving in the second year of reporting. Our EPR and packaging rules guide sets out how the bands are calculated.

Print and labelling on fibre materials

Fibre takes print differently from film, and the differences matter on a retail shelf. Uncoated kraft absorbs ink and drops roughly one full density step, so a photograph printed on kraft looks muted compared with the same file on a coated carton. If the artwork depends on accurate colour, either specify a coated board or shift the design to line work and a limited palette, which is what most outdoor brands do anyway.

Ink choice is a compliance question as well as an aesthetic one. Water-based flexographic inks are the default for paper and board, they cure without solvent recovery, and they do not interfere with repulping. UV-cured inks give sharper results but can complicate recycling if the film fraction is too high. Ask the print partner for a de-inkability statement rather than assuming, because it is the document an auditor will ask for.

Hang tags and labels are the last plastic to remove and the easiest to forget. A paper tag on jute twine, printed with the same water-based inks, costs a few cents more than a laminated tag on a plastic cord and removes the item most likely to be littered at point of sale. Our hang tag and label guide covers the material options, and our packaging ideas collection shows what the finished packs look like.

Compliance: EPR, labelling and claims

Extended producer responsibility shifts the cost of collecting and recycling packaging onto whoever places it on the market, and fee modulation is now the norm rather than the exception. Practically, this means you must be able to declare the material, the weight and the recyclability of every component you ship, per market, per year. A fibre-only pack makes that declaration straightforward; a mixed pack means every component has to be assessed separately.

Labelling is where programmes get into trouble. A carton printed with a recycling symbol and no qualification is an implied claim that the whole pack is recyclable in kerbside collection, and that is false if a compostable window film or a foil hot-stamp is present. Either remove the non-conforming element or qualify the claim with the correct instruction. Guidance on packaging and waste is published by the EPA, and it is a reasonable baseline even for programmes sold outside the United States.

Keep evidence. For every claim on the pack, hold one document that supports it: a mill certificate for recycled content, a repulpability test for the ink, a kerbside statement for the board. Audits are document-based and they arrive with short notice, and the programmes that pass are the ones where the evidence was collected at specification time rather than reconstructed afterwards.

Retail readiness and shelf presentation

Removing plastic changes how a bag presents on a shelf, and not always for the better. A polybag makes a bag look sealed and new; a kraft sleeve makes it look considered but shows every scuff from handling. If the bag is displayed unpacked, the sleeve comes off at the shelf edge and any scuff protection it provided is gone, so the bag itself has to be specified to survive being touched fifty times.

Three practical adjustments help. Use a sleeve with a die-cut window rather than a full wrap, so the colour and the welded seam are visible without opening the pack. Add a small printed band that carries the size and the waterproof rating, because that is the first thing a shopper looks for and a plain kraft sleeve hides it. And design the sleeve to tear off cleanly in one motion, since a sleeve that needs scissors gets destroyed by the shopper instead.

Shelf-ready packaging is a separate conversation worth having with the retail account before the pack is frozen. Some accounts want a carton that converts into a display tray with a perforated tear-off; others want individual sleeves with a euro-slot. Both are achievable in fibre, and both are cheaper to specify at the design stage than to retrofit. Our retail presentation guide covers the formats in detail.

Sampling and pack-out workflow

Change the pack at the sample stage, not at the bulk stage. Sampling runs take 6 to 10 working days and give you a real carton to test, whereas discovering at bulk that the sleeve scuffs will cost a reprint. Ask for two or three packaging options in the same sample shipment, run the drop and humidity tests on all of them, and choose with data rather than preference.

At pack-out, three small changes make the workflow work. Fit water-activated tape dispensers at every bench, because hand-tearing gummed tape is slow and the first week will otherwise be blamed on the material. Set a bench standard that sleeves are folded rather than crushed, since a crushed sleeve looks worse than no sleeve. And weigh a sample carton from every pallet to confirm the declared packaging weight matches the EPR filing.

Finally, brief the people packing. A fibre pack depends more on consistent folding and correct void placement than a polybag does, and variance shows up as damage. A one-page bench card with three photographs, in the language of the packing floor, does more for damage rates than any specification document. This is also the cheapest point at which to catch a carton grade that is marginal, because the packing team will report soft corners before any test does.

Measuring the change

• Plastic removed per unit in grams, measured on a scale rather than estimated from a drawing.
• Units per container before and after, to quantify the freight penalty honestly.
• Damage rate at destination, tracked for at least three months after the switch.
• EPR fee band before and after, taken from the actual assessment not a projection.
• Share of components with a supporting document on file, targeted at 100%.
• Retail returns attributed to packaging, separated from product returns.

Track damage separately from returns for the first quarter, because the two get conflated and the conflation hides the signal. A damage rate under 1% on a fibre pack is a good result for a soft product; anything above 2% means the board grade or the void fill needs another iteration. Do not revert to plastic on the strength of one bad pallet: find the lane, the handling point or the board grade that failed, because reverting loses the EPR benefit as well as the brand benefit.

Report the result internally in grams and in fee bands rather than as a percentage. Ninety-two thousand grams of plastic removed sounds less impressive than 100%, and it is also the number that appears in a compliance filing. Programmes that report in mass tend to keep improving, because the next target is obvious; programmes that report in percentages tend to declare victory and stop.

Trade-offs you should accept

Three compromises are unavoidable and should be agreed before the switch rather than discovered during it. First, fibre packaging is bulkier, so you will ship fewer units per container and your landed cost per unit will rise slightly. Second, sleeve print is less vivid than film print, so artwork built for a glossy polybag will need to be rebuilt for kraft. Third, humidity performance is genuinely worse, so tropical sea lanes need a better board or a desiccant.

What you get in return is a pack that can be declared in one line on an EPR filing, that a shopper can put straight into kerbside recycling, and that no longer generates the most visible form of litter at the point of sale. For a product sold into outdoor and watersports markets, where the buyer is acutely aware of plastic in the marine environment, that last point carries more weight than any of the costs above.

Marine debris is the context that makes this change worth arguing for internally. Packaging film that escapes collection is one of the most common items found on shorelines, and the NOAA Ocean Service publishes accessible material on where it comes from and how long it persists. A brand selling waterproof bags to people who use them on water is in a weak position if its own packaging turns up on the same beach.

Implementation checklist

• Write a written definition of plastic-free, including the exclusions, before ordering anything.
• Weigh every current packaging component on a scale and record grams per unit.
• Specify kraft sleeve, pulp or corrugated void fill, gummed tape and fibre twine.
• Run drop, vibration and 48-hour humidity tests on loaded cartons before committing.
• Upgrade the board grade for tropical sea lanes and add a desiccant if needed.
• Set print to water-based inks and request a de-inkability statement.
• Qualify every recycling symbol on the pack and hold one document per claim.
• Sample two or three packaging options and choose from test data, not preference.

A five-phase rollout keeps the risk low: audit ten samples in week one, substitute and test on fifty units in weeks two and three, validate on thirty units across three weeks, pilot with one account or one shipping lane at 500 units, then roll out with the EPR filing updated in the same cycle. Most programmes complete the whole sequence in under four months, and the pilot phase is the one that catches retail-handling problems that no laboratory test will find.

Our waterproof bag line has been produced since 2014 in an SGS-verified 4,950 m2 facility with seven lines and a 500-piece minimum, and packaging is specified at the same time as the bag rather than after it, which is the single decision that makes this change cheap. For the carbon side of the same decision, see our low-carbon production notes.

One closing point on honesty: the environmental benefit of a dry bag comes mostly from how long it lasts, not from what it ships in. A welded bag that serves ten years avoids ten purchases, and that dwarfs the 100 grams of packaging plastic in any reasonable calculation. Do the packaging change, declare it accurately, and then spend equal effort on the service life of the product, which is covered in our product life guide and across our eco-friendly dry bag range.