TL;DR
Compare the fabric families used in costumes, see what each one does well, and learn how weight, stretch, opacity and finishing change both the look and the production risk.
Knits for movement and fit
Polyester and cotton blend jersey, tricot and spandex blends are common for bodysuits, leggings and fitted dresses. They stretch, recover and accommodate a range of body shapes, which reduces the number of sizes needed for a good fit.
Weight matters here. A light jersey drapes and clings, while a heavier interlock holds shape and hides construction details. Ask for the fabric weight per square metre and a swatch before approving a fitted style.
Wovens for structure and drape
Satin, taffeta and polyester twill give shine and structure for capes, skirts and jackets. Satin drapes softly but shows every crease and stitch line; taffeta holds volume and rustles, which suits period and fairy styles.
These fabrics fray, so seam finishing is part of the specification. A costed style that omits overlocking or binding will show raw edges after a few wears.
Sheers for volume and effect
Tulle, organza and mesh create skirts, wings, veils and overlays. Tulle is available in a range of stiffness levels, and that stiffness, not the colour, determines whether a skirt stands out or falls flat.
Sheers are also where finishing quality is most visible: a raw tulle edge is acceptable on some designs and unacceptable on others, so define the finish rather than leaving it to the line.
Felts, fleece and novelty surfaces
Felt and fleece are used for hats, tabards, animal costumes and plush details because they hold shape, do not fray and accept applique. They can pill with abrasion, so check the surface after a rub test on any style intended for repeated wear.
Faux fur, sequin fabric and metallic knits add character but complicate cutting, packing and cleaning. Expect higher fabric waste and slower sewing on these materials.
Choosing by use, not by habit
Children's styles usually favour soft, opaque, easy care fabrics with simple closures. Adult fashion styles can carry sheers, structure and decorative surfaces. Accessories may need a heavier base than the garment they accompany.
Ask for a fabric card with weight, composition, stretch and a care recommendation for each material, then keep it with the approved sample. Shanghai Haitailu Clothing Co., Ltd builds its costume series around these fabric families, and each series page on www.festivocostumes.com lists the styles produced from them.
Related on this site: Browse costume series · Production categories · Discuss fabric options