Treat GSM as a direction, not the answer
GSM measures fabric weight per square metre. A higher number often feels heavier or denser, but yarn, construction, finishing and composition also change handfeel, drape and wear.
Work backward from the intended product
T-shirts can be developed from lighter midweight fabric through heavyweight options. Hoodies also need to balance season, inner construction, silhouette and the effect after washing. BIUSEE currently shows a common 180–500 GSM range; the approved sample remains the final reference.
- Lighter direction: prioritize season and breathability
- Heavier direction: check silhouette support and wearing volume
- Washes, prints and embroidery: test on the intended fabric first
Use an approved sample to lock the standard
Do not approve fabric by a number alone. Record composition, GSM, color, handfeel, post-wash change, measurements and decoration effect with the sample so bulk production has a clear reference.