Two rolls of non-woven can carry the same weight and behave differently, because the figure that matters is not the nominal value but where the process sits inside the tolerance.
What weight actually controls in non-woven
Cost driver and the only figure most buyers compare.
The consequence is that this figure sets the floor for everything downstream: the process, the price and the failure mode all follow from it.
For Non-woven fabric, the working range is 15-200 gsm. Inside that band the choice is commercial; outside it, the product changes category and so does the price.
What 15-200 gsm does not tell you
| Position | Value | Effect on non-woven | Where it shows up |
|---|---|---|---|
| Floor | 15 | Lowest cost, least margin for process variation | Weight shortfall within a season |
| Working middle | 15-200 gsm | Predictable performance at a normal price | Nothing to negotiate, nothing to explain |
| Ceiling | 200 gsm | Best performance, highest cost | Cost the end product may not recover |
The middle is where most programmes should sit, and it is the hardest position to defend in a price meeting because it has no story attached to it.
The figure that decides the outcome is not weight itself but the tolerance around it. A supplier who quotes 15-200 gsm without a tolerance has not quoted a specification, and the first lot will define the tolerance for you.
How to measure weight
The reference method here is Tensile strength, run to ISO 9073-3, with an acceptance of MD >= 20 N/5 cm, CD >= 12 N/5 cm. The method is the easy part; sampling and conditioning are where reports diverge.
Ask which instrument was used. For weight, two instruments that both claim the same standard can differ by enough to move a marginal lot from pass to fail.
Record the measured value rather than pass or fail. A marginal pass on weight tells you the process is running at the edge, which is the information you need before the next lot rather than after it.
Weight does not stand alone
Weight moves with tensile strength (MD 20-60 N/5 cm) and with elongation (20-80 %). Tightening one usually costs money in another, and a supplier who accepts every tolerance without comment has either not understood the interaction or is planning to substitute.
When you change weight, re-check the two neighbours before you approve the sample. Most of the samples we re-make are caused by a change in one figure that was not followed through.
The clause to write for weight
The line below is the version we can quote against without inventing anything. Weight appears with a tolerance and a test, not as a standalone number.
Polypropylene spunbond, 80 gsm +/- 5 %, 160 cm, MD tensile >= 30 N/5 cm, CD >= 18 N/5 cm, UV stabilised, Pantone 19-3906 TCX
The clause that protects you is not the value, it is the sentence that says what happens when the value is missed. Put it in the purchase order, not only in the enquiry.
When weight goes wrong
Weight shortfall. The roll weighs less than ordered and the cover feels thin.
The cause is usually nominal gsm quoted from the line setting, not the delivered goods.
The test that catches it: ISO 9073-1 mass per unit area on three samples per lot.
What to specify instead: Buy on measured gsm with a +/- 5 % tolerance written into the PO.
None of this is visible in a quotation. It becomes visible in a retained sample and a lot record, which is why the paperwork matters more than the price on this parameter.
Four questions about weight, before you order
- What tolerance do you hold on weight, and what did your last three lots measure against it?
- Which method do you use for tensile strength, and which laboratory signs the report?
- When weight falls outside 15-200 gsm, do you rework, downgrade, or ship and hope?
- Which of tensile strength or elongation would you move first to hit a lower price?
The answers are more useful than a certificate, because they show whether the process is controlled or merely inspected. Full ranges for non-woven are on the product page, and the measurement regime is described on the quality control page.
Questions buyers ask before ordering
Can you supply UV-stabilised material?
Yes, with a stated exposure period. ‘UV treated’ without hours or months is not a specification.
What is the MOQ for a custom colour?
1000-2000 kg for masterbatch colour; white and black from stock.
Seven lines that turn a quotation into a specification
Most post-delivery arguments are not about quality. They are about a document that never said which figure would be measured, on which instrument, at whose cost.
- Elongation (20-80 %): fix the value per shipment, and state who pays for the re-test if a lot lands outside it.
- Width: 160-320 cm is not an answer on its own. Ask for the last three lots’ actual readings and the spread behind them.
- Hydrophilic / hydrophobic: agree the test method with the number. Two labs, two methods, two answers, one argument.
- Colour fastness (>= grade 3-4): state where in the band this order sits. The middle of the band is not what a tolerance is for.
- Price validity: the period during which the quoted figure holds, and what happens to it when the raw-material index moves.
- Remedy: rework, replacement or credit, and the point at which each applies.
- Sample retention: one production sample per lot stays with the mill for twelve months. Claims are settled against it, not against memory.
Three questions, and the answers that separate mills
If the non-woven figures on this page is going to be decided on a call, take these three questions into it.
| Question | Answer that should worry you | Answer that holds up |
|---|---|---|
| Which test catches low cd strength? | “We have never had a complaint.” | Elongation — on the production lot, with the acceptance figure written into the report and not into the email. |
| May I see a report for a lot you shipped last month? | “That is confidential customer information.” | A redacted report, which carries every number that matters and none of the customer’s identity. |
| Where in the 160-320 cm band will this order sit? | “In the middle, normally.” | A stated target and the readings behind it. Width drifting inside the band is how a conforming lot still fails. |
Need weight specified and tested against your end use?
Send the end use, the quantity and the destination market, and we will come back with a specification that meets it, a price at your volume and the test reports that back it up. Samples are free for qualified programmes; we charge the courier only.
Related reading
- Non-woven fabric Specification
- How to Test Non-Woven Before You Commit to a Container
- Process in Non-woven fabric
Sample cut with your values on it · Neutral packing and private label · Consolidation, documents and lead times
