Pattern Alteration

June 18, 2025 - June 18, 2025
At some points you may need to alter either a brought pattern or a pattern you have previously done yourself by reducing or enlarging, grading up or grading down.
To reduce the measurements of a pattern
At the appropriate position crease the paper and make a pleat equal in the width to half the amount that needs to be reduced, pin into position. For alterations in width, the excess amount should be divided between the back and the front and equally between left and right side of the garment.
- Pleats pinned in back and front to reduce width at shoulder, bust and waistline
- Reduce the armhole by pinning a piece of paper behind the pattern and drawing in a new line to raise the under-arm.
- Width of shoulder reduced from shoulder to wrist
- Length of sleeve reduced between shoulder and elbow and elbow and wrist
- Correction of seam line
- Length of skirt reduced between hips and hemline
- Position line for reduction in width of waist, hip and hemline.
To enlarge the measurements of a pattern
At the appropriate position line cut through the paper pattern an place over a strip of paper so that the edges of the pattern are parallel, the width between equal to the amount to be increased. For alterations in width the additional amount should be divided between back and front and equally between left and right sides of the garment. For example to increase the bust and waist measurements by 5cm insert 1.25cm strip from shoulder to waist in each quarter of the bodice. Re-draw the seam line across the insertions.
Note if the armhole is reduced the sleeve must also be reduced. The waist reductions must be made on both the bodice and a skirt.
- Strip inserted to increase width at shoulder, bust and waistline.
- Position line for increasing length from neck to waistline between under bust and waist.
- Dotted line indicates the area to be trimmed away to enlarge the armhole, check the same length of under arm seam is removed from back and front bodice.
- Width of sleeve increased from shoulder to wrist
- Sleeve lengthened between shoulder and elbow and between elbow and wrist.
- Seam line re-drawn and sleeve head deepened.
- Skirt lengthened between hip and hemline
Note: always add a 1cm seam allowance when pattern cutting, if altering a pattern that has already been made always add the 1cm seam allowance at all areas that have been changed.