Body and sleeve length are the easiest parts of a garment to change. They are mostly straight fabric, and adding or removing rows does not disturb the armhole or neck shaping — as long as you make the change in the right place.

The rule is simple: adjust the straight sections, not the shaped ones, and keep the stitch pattern's repeat intact.

Body length

For a straight body, add or remove rows above the hem ribbing and below the armhole. That keeps the hem and the armhole where the pattern put them.

  1. Decide the extra length in centimetres.
  2. Multiply by your row gauge to get the number of rows.
  3. Adjust the row count to the stitch pattern's vertical repeat.
  4. Add the rows before the armhole shaping, not in the middle of a cable or lace repeat.

A worked example

The pattern's body is 58 cm; you want 62 cm. Your row gauge is 3.2 rows per cm, so 4 cm needs about 13 rows. If the stitch pattern repeats every 6 rows, add 12 or 18 rows rather than 13, so the repeat stays intact.

If you add 12 rows, the body is 61.75 cm; if you add 18, it is 63.6 cm. Choose the one closer to the length you want. The difference is small, and the pattern repeat is preserved.

Remember to allow extra yarn for the added length. A few rows on a sweater body can consume a surprising amount of yarn.

Sleeve length

For a sleeve worked from the cuff up, add or remove rows before the underarm shaping. For a sleeve worked from the top down, add or remove rows below the cap. In both cases, keep the cuff and the cap where the pattern placed them.

If the sleeve has increases, spread them across the new row count rather than adding all the extra rows at one end. The increase rate should stay roughly proportional, or the sleeve will change shape.

What not to change casually

  • Armhole depth. Changing the armhole changes the sleeve cap and the shoulder fit; it is a re-grade, not a length adjustment.
  • Body width. Adding stitches to the width changes the armhole and the neck; use a size change or a gauge recalculation instead.
  • A shaped hem. A curved or stepped hem has its own row counts; adjust above it or re-chart it.
  • Colourwork bands. Adding rows inside a colourwork chart changes the design; add plain rows above or below the band.

Check the schematic

Mark the new length on the schematic and check it against the armhole and sleeve. A longer body may change where the pockets, waist shaping or buttonholes sit; move those features with the length rather than leaving them at the old position.

Yarn quantity for a length change

Adding rows uses more yarn. Estimate the extra fabric area and multiply by the swatch weight, or add 5–10% to the project quantity for a small length change. A longer body can push a project into an extra skein, especially in a large size.

For a top-down body, add the rows below the armhole rather than above the hem, so the armhole depth stays correct. The same principle applies: adjust the straight section, keep the shaped section. Record the new row counts in the pattern so the change is reproducible.

Limits

Length changes are safest on simple shapes. A tailored garment with waist shaping, a curved hem or a fitted sleeve cap has more interconnected numbers; at that point, a pattern with a different length may be the better choice.

Use row gauge to convert the change into rows, then adjust the shaping.

Sources