Sometimes it’s necessary to alter existing clothes for a better fit. Here Janet Moville provides some professional tips for the most common alterations

Trousers and Skirts – Hem Allowances

  • Let down existing hem if necessary before marking new hemline.
  • Allow 3 cm (1 ¼”) for jeans that will be pressed into a narrow double hem and 4 cm (1 ½”) for trousers and skirts.
  • Full skirts need a narrower hem of 2.5cm (1”) for a hand stitched blind hem method or you may prefer to machine narrow hem in which case 6-10 mm (1/4 – 3/8”) is all that is required.


Mark the new cutting line by measuring up from the existing hem line and marking with a cloth marking pencil, trick marker or chalk wheel.
Example: Trousers need shortening by 9 cm (3 ½”). Hem allowance required is 4 cm (1 ½”). Measure up from existing hem 5 cm 2” all the way around to mark cutting line.

  • Carefully trim away surplus fabric.
  • Prepare the hem by using one of the following methods (no need to prepare jeans):
  • Overlock the raw edges using an overlocker or an overcast machine stitch.
    HANDY HINT: Separate the side seams before overlocking, then re-sew the seams. The hems will lie flatter!
  • Sew seam tape or bias binding tape to cover the edges.
  • Cut bias strips of lining or cotton lawn to apply custom made bias binding using a tape maker.
  • Now press up the hem allowance to the underside of the hem using a sewing gauge set at the required amount. Take care to set the iron at a temperature compatible with the fabrics’ fibre content. Pressing too heavily will cause shine. Use a press cloth or an iron shoe and allow the steam to do most of the work.
    HANDY HINT: A point presser and clapper is a useful pressing tool, but a smooth block of hard wood works just as well.
  • Complete the hem by hand sewing using a blind hem or locking stitch. A topstitched hem using a wide twin needle can make a fashionable alternative to hand stitching.


At this stage you will have pressed up 3 cm (1 ¼”). Now open up the fold and position the raw edge to the crease line, pressing a new narrower fold. Fold in again creating a double fold.15 mm (5/8”) deep. Machine stitch the hem close to the fold line.

HANDY HINT: Reducing the presser foot pressure will help the machine to ride over thick seams. Using a tool nicknamed a ‘hump jumper’ or folding a piece of fabric and placing it behind the machine and under the back of the foot will also help the machine to feed. If the foot is tilting backward it cannot grab the fabric. Raising the foot at the back improves friction.

Lined Jacket Hems and Sleeves

  • Let down existing hem before marking new hemline.
  • Allow 4-5 cm (1 ½”-2”) hem.
  • Trim away surplus. Trim same amount from lining.
  • Fix new strip of fusible interfacing to hem allowance of main garment. Press up new hem allowance. Use a sleeve board where necessary.
  • Sew seam allowances together within hem to secure.
  • Sew lining to garment using bagging out method or press up 15 mm (5/8”) on lining and slip stitch in place.
    HANDY HINT: Use a strip of Bondahem between the fold to secure one piece sleeve hems and wide sections of jackets and coats.

Skirt Waistband Alterations

Letting out

Remove waistband to let out skirts through the waist. If the seams allowances are too narrow to provide sufficient room, shortening from the waist can provide that little extra. If there is insufficient fabric in the waistband:

  • Use the zip guard
  • Replace with petasham or petastretch
  • Use the lining to finished the edge and omit the waistband altogether.

Taking in

  • Remove the band partially to beyond the side seam on the left hip.
  • Try on the skirt and pin out the excess at the side seams.
  • Turn the skirt inside out and use a cloth marking pencil or chalk wheel to mark the new stitching line along the pins.
  • Remove pins, sew along the new fitting line blending the shape smoothly back into the original seam line.
  • Re-fit the waistband to the skirt removing the excess fabric from the right back edge.
  • Sew back in place.

For adjustments that don’t affect the waist follow steps 2 – 4.

Sway back adjustments

  • Remove waist band from back section only between side seams.
  • Tie narrow elastic around waist. Chalk underneath the elastic across the back skirt waistline.
  • This is the new sewing line. Allow a seam allowance equal to the rest of the skirt. Trim away excess.
  • Replace the waist band.

Trouser Waistband Adjustments

Letting out

This is only possible if the waistband has a seam at centre back.

  • Remove the stitching from the ditch of the waistband seam at centre back for around 8 cm (3”) at either side.
  • Lift the band open. Remove the stitching from the centre back seam to hip level only.
  • Re-sew the centre back, letting out the amount required and blending smoothly into the original seam.
  • Press seams open. Re-fold waistband before stitching in the ditch as before.

Taking in
Follow same procedure, taking in amount required at step 3

Princess Seam Adjustments

These are the easiest to alter as small amounts can be taken at each seam and shaped to the individual figure.
Analyse the figure before deciding where to make the adjustments. For instance, a full tummy and a narrow back / flat seat will require most of the adjustments made to the back of the garment.
A broad back and small bust will require most of the adjustments at the bust line.

Shoulder / Sleeve Adjustments


It is important to consider the ‘cause and effect’ that alterations will have on other parts of the garment; none more so than shoulder adjustments. Attempting to narrow a shoulder, even by using princess seams to do this can adversely affect the pitch of the sleeve, causing diagonal drag lines to develop. Always pin out the intended alteration to check the possibilities before proceeding.

It may be possible to correct this by removing the sleeve completely and trimming the underarm sleeve seam, thus deepening and adding height to the sleeve head. The knock on effect of this though would be to shorten the sleeve by the amount trimmed from the under-arm. Mark and pin the intended alteration in place before trimming as it won’t be possible to rectify later.

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