GSM / Fabric Weight

GSM (grams per square meter) is a measure of fabric weight, and for drapery and roman-shade textiles it’s a useful proxy for how a panel will behave: heavier fabrics hang with more body, resist light better, insulate a touch more, and drape into fuller folds, while lighter fabrics float, filter more light, and read airy. It isn’t a quality grade — the right weight depends on the job (a breezy sheer wants low GSM; a room-darkening drape wants high) — but where a seller publishes it, it lets you compare beyond a photo. Pair GSM with the lining choice, since backing a light fabric can add the opacity the weave lacks.