August 22, 2016

How to sew a side seam with French seams and slits


I love using French seams, but they present a little bit of a challenge if there’s something else on that seam like a zipper, or  side seam slits, like on the Springfield Top. Here’s how I approach it – if you know any other techniques, let me know!

  1. Pin the front and back together at the side seams, WRONG SIDES together. Use chalk or a different pin colour to mark where the side slit starts.

Side seam with French seams and slits

2. Sew down the side seam to the slit marking, at a 1/4″ (6mm) seam allowance. Stop and backstitch at the slit marking. Trim the seam allowance that you’ve sewn (but NOT the slit part) down to 1/8″ (3mm).

Side seam with French seams and slits

3. Press the seam, then fold the side seam RIGHT SIDES TOGETHER, sandwiching the seam allowance inside the two pieces of fabric. Pin, again marking the height of the side slit.

Side seam with French seams and slits

4. Sew down the side seam again, at a 1/4″ (6mm) seam allowance, stopping and back stitching again at the top of the slit.

Side seam with French seams and slits

5. Very carefully, use scissors to snip into the seam allowance at the top of the side seam, right up to, but not through, the stitching. This “releases” the fabric from the French seam.

Side seam with French seams and slits

6. Press French seam to once side.

Side seam with French seams and slits

7. Finish slit by turning the raw edge to the wrong side by 1/4″ (6mm) and pressing, then repeating another 1/4″ (6mm) and pressing. Do this on both sides.

Side seam with French seams and slits

8. From the right side, sew up one side of the slit, across the top, catching the bottom of the French seam to secure it, and then down the other side. You may find using lots of pins or Wonder tape will help everything stay where it’s meant to be! You can also sew from the wrong side to make it a little easier (just make sure you have the right bobbin colour in your machine).

Side seam with French seams and slits

And there you have it! You’ve sewn a side seam with French seams and slits.

Side seam with French seams and slits

3 thoughts on “How to sew a side seam with French seams and slits

  1. PsychicKathleen says:

    This was very helpful Jenny. I love french seams and use them often but there are spots when they become awkward (bulky) and I never know how to manage them. You’ve given me some ideas!

  2. Vivid Kitty says:

    This is really useful. I recently made a top with French side seams and suits and just had to fudge it. It was good enough in the end, not as dlick as this. Thanks, Jx

  3. This is how I do it, too. I usually put a little Fray Check at the tops of the slit turn unders where there is a raw edge. I’m hoping for another technique to try. Anyone know a good one?

Let me know what you think!