Irha Apparels · B2B Manufacturing Guide

How to Choose GSM for Custom T-Shirts, Hoodies and Sweatshirts

GSM means grams per square metre. It describes fabric mass per area, but it does not by itself prove softness, strength, warmth, opacity, shrinkage performance or overall garment quality. Two fabrics with the same GSM can behave differently because the fibre composition, yarn, knit structure, brushing, compacting, dyeing and finishing are different.

Start with the intended product

Define whether the garment is a lightweight layer, an everyday T-shirt, a structured oversized style, a warm hoodie, a loopback sweatshirt or another specific product. Explain the target climate, retail position, fit and expected hand feel. A useful request describes the result the buyer wants instead of using GSM as the only quality instruction.

Confirm the full fabric specification

Record composition, knit or weave, target GSM, colour, finish, stretch direction, surface appearance and shrinkage expectations. For fleece and French terry, also confirm the inside construction. For rib components, specify where they are used and how their recovery should relate to the main fabric.

Review a physical sample

Approve fabric and garment behaviour together. Check drape, opacity, recovery, collar or rib stability, seam appearance and the result after the agreed care test. A small fabric swatch helps with hand feel, while a garment sample is needed to review fit and construction.

Keep quotation inputs connected

Fabric choice affects consumption, decoration compatibility, handling, packing and freight. Send the intended quantity, colours, size range, branding, packaging and destination with the material direction so feasibility, sampling and commercial terms can be reviewed for the actual program.

Practical RFQ checklist

Product type and intended use Composition and preferred fabric construction Target GSM as a direction, not a quality guarantee Fit, measurement chart and tolerance proposal Colour and finish requirements Printing, embroidery or other decoration Labels, hangtags and packaging Quantity, size split, destination and requested trade term

Final material, MOQ, price and production timing should be confirmed only after the complete brief and available material options are reviewed.