Bags are the harshest test for a woven fabric: abrasion at the base, flex fatigue at the zip, point loads at the strap anchors. Most bag failures are seam failures, and seams fail because the coating — not the yarn — gave way.
Choosing the denier by bag type
| Bag type | Fabric | Why |
|---|---|---|
| Promotional tote | 300D PU, 1,000 mm | Cost-driven, light loads |
| School / daypack | 600D PU, 3,000 mm | Balance of abrasion and price |
| Travel / luggage | 600-900D with PU or TPU | Flex fatigue at the base corners |
| Tool / motorcycle | 1680D PVC or TPU | Point loads and abrasion |
Seam strength is the real spec
Ask for the fabric’s tongue tear strength and then test a sewn seam: a 600D with 25 N tear strength can still fail at the stitch line if the coating is brittle. Coating elongation matters as much as fabric strength — a rigid PVC coating cracks when the seam flexes.
Waterproofing that matches the claim
- Water repellent (DWR) — rain beads off, seams still leak. Do not call this waterproof.
- 3,000 mm — rain-resistant for a daypack.
- 10,000 mm+ — genuinely waterproof, requires taped seams to mean anything.
Ordering notes
MOQ 800 m per colour, sampling 5-7 days, production 15-25 days. Because bags are cut in panels, order 8-12% extra for wastage on printed or directional fabrics. See the bags and luggage fabric range, and our applications page for how the fabric behaves in finished products.
Construction details that fail first
- Base corners — the highest abrasion point; specify a reinforced panel or a heavier denier there.
- Zip tape — usually a different supplier’s product; a water-resistant zip with an untreated tape leaks.
- Strap anchors — point loads concentrate at four stitch points; bar-tack rather than single stitch.
- Lining — 210D is standard; below that, the lining tears before the shell wears out.
How the quote is built
Denier, coating type and coating weight drive 70% of fabric cost. A 600D PU at 3,000 mm is a different product from 600D PU at 1,000 mm, and the price difference is roughly 20-30%. For a bag sold with a “water resistant” claim, the cheaper option is adequate; for “waterproof”, it is not.
Also budget for 8-12% wastage on printed or directional fabric, and confirm whether the mill delivers full rolls or cut lengths — cut lengths add a per-metre charge.
Related guides
Send the bag type and target retail price. We will recommend the construction that survives the abuse profile without over-specifying.
Sample cut with your values on it · Neutral packing and private label · Consolidation, documents and lead times
