Garment Finishing
Pleating is bought by the finished metre and cut by the flat metre. Between them sits a multiple that is easy to underestimate.
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Flat fabric per unit of finished width
Pure geometry: it takes no account of the fabric thickness that stops folds closing fully, nor of the shrinkage a heat-set pleat undergoes. Sunburst pleats vary the fold depth along the panel, so run this at both the narrow and wide ends and cut for the larger.
Pleating Take-up Ratio & Flat Fabric Requirement — free, with the formula and a worked example, at Textile School.