Custom Printed Quad Seal Bags for Heavy Fills up to 5 kg

How is a quad seal bag made?

Start with a side gusset bag, the kind used for coffee for decades. Now run a heat seal down each of the four vertical corners where the gussets meet the front and back.

Those four seals are the whole point. They stiffen the corners so the bag stands square even when it holds 2 kg of kibble, and they give four clean panels for print.

The base is pinched and sealed rather than a separate panel, so the bag is simpler to make than a flat bottom pouch and takes a heavier load. Compare it with our plain side gusset bags without corner seals to see the difference the seals make.

Which products need a quad seal bag?

Heavy, dense products that a stand up pouch cannot hold straight. Flour and sugar at 1 kg to 2 kg. Rice and pulses in 2 kg to 5 kg trade bags. Dry dog and cat food in the 2 kg to 5 kg range.

Roasters packing 1 kg and 2 kg bags for cafes often choose the quad seal with a valve. It stacks on a shelf and stays square in a delivery crate.

Millers and dried goods packers can see worked sizes on our flour and dried goods bags page.

• Plain, bread and speciality flours from 1 kg to 5 kg
• Rice, lentils, chickpeas and dried beans
• Dry dog and cat food, 1.5 kg to 5 kg
• Wholesale coffee in 1 kg and 2 kg bags
• Bird seed and small animal feed
• Bulk sugar, salt and bakery mixes

What size quad seal bag holds 1 kg of flour or 2 kg of dog food?

Flour packs tightly, about 0.6 g per ml, so 1 kg needs around 1.7 litres. A 140 × 340 mm bag with an 80 mm gusset covers it with room for the top seal.

Dry dog food is lighter and lumpier, so 2 kg needs about 4 litres. That means a 170 × 400 mm bag with a 100 mm gusset.

The gusset is the lever. A deeper gusset adds volume without making the bag taller, and a shorter, deeper bag stands more steadily. For fills under 500 g, our stand up pouch size guide for lighter fills is the right place to start.

Laminate and gauge for heavy fills

Weight changes the laminate choice. A 5 kg bag needs a thicker PE layer so the base seal does not split when the bag is dropped onto a pallet.

Kraft / PET / PE gives a flour mill or a feed brand the paper look at 1 kg to 2 kg. PET / foil / PE suits coffee and anything that needs a long shelf life. Matte BOPP / PE is the lighter option for pet treats with a window.

Food-contact, high-barrier and compostable film options are available on request, and the quote states the gauge we recommend for your weight. Each structure is set out in our guide, barrier films and laminates explained.

Top closures: heat seal, zipper or tin tie

Most quad seal bags are heat sealed across the top after filling. For a 5 kg bag of rice that is used in one go, nothing else is needed.

A press-to-close zipper suits 1 kg and 2 kg bags of pet food or coffee that are opened daily. The zipper sits below the top seal and the customer tears the notch to reach it.

A tin tie is a folded wire strip stuck to the top. It is the cheapest reclosable option and the one most coffee roasters already know. A one-way degassing valve fits a side gusset or the front panel for coffee packed fresh.

Printing four panels on a quad seal bag

The front and back are full panels. The two gussets are narrower but run the full height, which makes them ideal for a feeding guide, brew notes or a long ingredients list.

The corner seals are about 8 mm wide and printable, so a colour change at the corner looks deliberate. Keep text 5 mm clear of each seal, as our artwork and dieline guide for pouches shows.

Full colour plate print is the usual choice at the quantities these bags run at. Digital print is available for shorter runs and trials.

How do you fill a quad seal bag by hand or on a line?

Quad seal bags are filled through the open top. The corner seals mean the bag opens square with little coaxing.

1. Stand the empty bag in a bag holder or a carton that matches its footprint.
2. Push the gussets out so all four corners sit square.
3. Fill by weight, keeping product at least 40 mm below the top edge.
4. Shake the bag down, then seal the top on a bar sealer wide enough for the full width plus gussets.
5. For zipper bags, close the zipper before the heat seal above it.
6. Stack sealed bags on their base, never on their side, for the first hour.

Common problems with quad seal bags

A bag that leans. Usually the gusset is too shallow for the height, so the base is narrower than the bag is tall. Go deeper on the gusset.

Base seals that split. The laminate is too light for the weight, or the bag was dropped flat on its base from a height. The heavier gauge fixes it. A split caused by a film fault is covered by our misprint and damage reporting terms when reported within 10 days.

Top seals that wrinkle at the gussets. The sealer bar is too narrow and does not reach the folded layers at each end. A wider bar or a double seal solves it.

Valves placed on the back where the shelf hides them. The valve goes on a gusset or the front so it is visible in the warehouse check.

Is a quad seal bag better than a stand up pouch?

For light fills under 500 g, no. A stand up pouch is cheaper, uses less film and stands well at that weight.

For 1 kg and above, yes. The four corner seals and the deeper gussets keep the bag upright and square, and the pinched base takes the load.

Between 500 g and 1 kg it is a judgement call. If the bag sells on a shelf, the quad seal looks more like a branded box. If it sells online in a mailer, our stand up pouch range for lighter fills is enough.

Ordering quad seal bags

Send us the product, the fill weight, the closure, whether you need a valve, and the number of bags. Prices start from £0.25 per unit and the written quote confirms the figure for your run and gauge.

Our designers set the four panels on a dieline and send a free proof. Once approved, production takes 4–6 business days. To compare this bag against the rest, see every pouch style we print on one page.

Free tracked UK delivery follows in 2–3 business days. Misprinted or damaged bags are reprinted or refunded when you report them within 10 days with photos.