the body (use the waist or trouser waist measurement). On trousers with elasticised waistbands, the length will be determined by the waist measurement of the pattern. The waistband depth can vary but it is usually approximately 4cm. The waistband of formal trousers usually has a back seam. There is often a 3cm seam allowance (inlay) on this seam; this inlay means that a trouser waistline can be altered.
1a Single cloth waistband Draw two rectangles: A-B is 1/2 waistband length required; B-D is the waistband depth plus 2cm for seam allowance. B-E 0.5cm; join D-E. A-F is the width of fly extension. A-G is the width of button extension. Add seam allowances to edges where shown. A single cloth waistband has a top seam and is usually self-faced. Some formal trousers are faced with a 'shirt-gripper ' band. In this case, cloth facings are cut for the fly and button extensions.
1b Tailored waistband with slide adjusters The waistband is cut from the single cloth waistband. Construct the waistband 1a, but add 2.5cm to measurement A-B. A-H is 1/2 measurement A-B; square up.