Fix a Fallen Hem So It Disappears

By the end of this half hour you will have a pair of trousers (or a skirt, or a lined coat) back in your rotation with a hem that holds and shows nothing at all from the right side. This is the smallest possible sewing project that saves a real garment, and it needs no machine, no pattern and no sewing room — a needle, matched thread and a flat surface will do it.

It is also the first place most beginners meet the slip stitch, the stitch that hides itself inside a fold. Learn it here, on a garment you had already half given up on.

What you need

Everything here is reusable across every future project, so the cost is a one-time thing rather than a per-repair thing.

Numbers to know

There is no cutting in this project, so there is no cut list — but there are a few measurements worth having in your head before you start.

• Thread length: about 18 inches. Longer thread feels efficient and then tangles, which is a much slower problem than re-threading.
• Hem allowance: the folded-up fabric inside a trouser hem is usually 1 to 2 inches deep. Whatever yours measures, that is the depth you are restoring — do not adjust it.
• Repair overlap: start and finish your stitching about 1 inch inside the intact original stitching on each side. That overlap is what stops the repair unzipping again from the ends.
• Stitch spacing: about a quarter-inch between stitches. Closer is stronger but stiffer; wider is faster but starts to sag between stitches.
• Bite depth: catch one or two threads of the outer fabric per stitch. That is genuinely all.

Steps

Prepare the hem

1. Turn the garment inside out and lay it flat with the fallen section facing you. Working from the inside is the whole trick — everything you do from here happens on a surface nobody sees.
2. Remove any loose old thread. Pull broken tails out by hand, using a seam ripper only where they are still anchored. Thread left in the fold creates lumps that show through the finished hem.
3. Fold the hem back up along its original crease. There will be a pressed line and often a faint needle-mark line from the factory stitching. Follow them — that crease is a free, accurate guide you could not mark straighter by eye.
4. Press the fold with a warm iron, matching the heat to the fabric type. Pressing sets the fold so it stops fighting you while you stitch, and a set fold is far easier to sew invisibly than one you have to hold in place.
5. Pin every 2 to 3 inches, placing pins perpendicular to the fold so they are easy to pull out as you go.

Stitch the slip stitch

6. Thread the needle and tie a knot in the long end. If threading is fiddly, cut the thread end at an angle and press it flat between your fingernails first. Working with a single thread rather than a doubled one keeps the repair flexible — the same logic as any of the basic hand sewing stitches.
7. Bury the knot inside the fold. Bring the needle up through the folded edge only, an inch inside the intact stitching, so the knot sits hidden between the layers rather than sitting proud where it can catch.
8. Take a tiny bite of the garment fabric directly opposite where the thread emerged — one or two threads' worth, no more. This is the only stitch that touches the outside of the garment, and its whole job is to be too small to see.
9. Slide the needle back into the fold and travel about a quarter-inch inside the folded edge before coming out again. The thread is now hidden in the tunnel of the fold, which is why the finished line reads as blank fabric from outside.
10. Repeat: tiny bite, quarter-inch slide. Keep the thread relaxed. Pulling each stitch tight is the usual cause of the puckered, dimpled hem line you have seen on badly repaired trousers — the stitches should lie, not grip.
11. Check the right side every 4 or 5 inches. Turn the garment over and look. Catching a too-deep bite after five stitches costs you five stitches; catching it after fifty costs you the afternoon.

Finish and press

12. Overlap the original stitching by about an inch at the far end, then anchor with two or three small stitches worked in the same spot, inside the fold.
13. Knot and bury the tail. Make your knot close to the fabric, then run the needle through the fold for an inch before cutting. The tail ends up trapped inside where it cannot work loose.
14. Press the finished hem from the inside, then from the outside with a cloth between iron and garment if the fabric has any sheen. Pressing settles the stitches into the fabric, and it is genuinely the moment the repair becomes invisible.

When it goes wonky

Wonky is the expected outcome the first time, and almost all of it is fixable from the inside where nobody will ever know.

What you just learned

• The slip stitch — the invisible-finish stitch used on hems, linings, bag openings and the closing gap of anything you turn right-side-out.
• Pressing as a construction step, not a tidying step. A pressed fold is a fold that stitches accurately.
• Reading a garment's original construction — following factory creases and stitch lines instead of inventing your own placement.
• Anchoring and burying thread so a repair ends where it should rather than unravelling from the ends.

Next, take the same needle to the Sew On a Button project in the library — it uses the same knot-burying finish on a different anchor — or browse everything else you can make without a machine on the Curious level page. When you eventually want to shorten a pair rather than rescue one, how to hem trousers picks up exactly where this leaves off.