Closed seams cannot hide behind closed doors as they are the signature of high-end clothing. No frayed looks or shabby stitching for Haute Couture’s best designs. No, it is closed seams all the way! Why you might ask? Closed seams give the classical look and finish of what is expected from the best fashion houses. Closed seams neaten the seam in a way that adds to the quality of the garment.
Closed seams are the exact opposite of open seams because everything from the seam allowance and the raw edges is enclosed in the finishing off of the seam. Seams are the process that puts the garment together. Every little detail is taken care of with a closed seam. There are different types of closed seams, but the principle is the same. The entire seam is neatened and there are no raw edges sticking out at the end of the process.
In a closed seam, the seam allowance is either pressed to one side or encased in the fabric entirely. Contrast this to an open seam where the seam allowances are pressed open and then the edges are finished.
It is important to choose the best kind of closed seam to suit your fabric and the garment you are making. French seams, for example, are better for lightweight fabrics. A flat felled seam is better for tougher fabrics like denim. The stitch length is important too for the success of the seam, especially with bulky fabrics.
Types of Closed Seams
Here are 7 kinds of closed seams to consider. Each seam is different and suited to different purposes and types of fabrics, but the outcome is the same, a closed seam.
- Zig-Zag Closed Seams
- Overcast Closed Seams
- French Seams
- Bound Seams
- Welt Seams
- Lapped Seams
- Fell Seams
Stitch the seam with a straight stitch at the seam allowance. Then press the raw edges to one side and use a wide zig-zag stitch to finish. It is best to sew a little in from the raw edge to prevent puckering of the stitches.
Overcast stitches are a specialty stitch on a regular sewing machine designed to mimic a serged edge. Unlike a serger, an overcast stitch does not cut and sew at the same time. It is important to start with a clean raw edge.
French Closed Seams
French seams are ideal for delicate fabrics like chiffon and organza. There is a fair amount of material that goes into the seam when it is enclosed. The French seam is therefore not suited to heavier fabrics because the seam can become bulky. The edges of the seam do not show with a French seam and this makes it a great seam for sheer fabrics. The French seam is best suited to straight seams.
How to Sew a French Seam
- NEATEN – Make sure your fabric is cut carefully and neaten up any stray ends on the edge of the seam allowance. You need clean cut edges for this seam.
- STITCH – You will be working with the wrong sides together initially. This is the opposite of a normal seam. Start by subtracting ¼” from your seam allowance marked on your pattern. If your seam allowance is 5/8” then you will sew your initial seam with a 3/8” seam allowance.
- TRIM – Trim the seam allowance down to a 1/8” and press the seam as it was sewn. Do not press the first stage of the French seam open. It is important to just press firmly on the seam and not iron with side-to-side movements because you just want to set the seam and not pull it in any way.
- FOLD – Fold the fabric along the seam line. This fold will bring the right sides together. Press again firmly on the seam. Pin the fabric firmly in place. Now the raw edges are enclosed in the French seam. Check for any threads or raw edges and snip them off or push them into the seam. It is advisable not to pull threads as this may cause the frayed edges to be worse.
- STITCH – Sew a second seam 1/4 inch in from the folded edge. This seam must completely enclose the first seam and its raw edges.
- PRESS – Press the seam towards the back of the garment. Then turn over the fabric to the right side and press again. Voila, as the French would say – you have completed a French seam.
- FULL ARTICLE – How to sew a French seam
Sewing a French Seam on a Curved Edge
While not advisable because the French seam is best suited to straight seams, it can be done. Sometimes a French seam may look best along a curved seam if you want to lose bulk from the seam. This depends on the fabric and the part of the garment to be joined.
Bound Closed Seams
A bias bound seam is finished off with bias tape to neaten and enclose the raw edges. This seam gives a neat finish that solves the problem of raw edges fraying. The bias-bound seam can bind the raw edges of the seam together or separately. Bound seams finish off an unlined jacket very nicely because the bias can be a contrasting fabric adding some detail to the finished garment.
There are 2 ways to sew a bias bound seam.
Method #1 – Hong Kong Finish
- Prepare your seam as normal and stitch the seam with the right sides together.
- Press the seam either open or to the side.
- Prepare the bias tape, either store-bought, or you could make your own. Usually, this method is done with half-inch single fold tape.
- Open up one side of the tape and match it to the raw edges of the seam.
- Stitch in the first crease which is 1/4 inch in from the edge.
- Fold the tape over to the back of the seam.
- Stitch in the ditch on the top of the seam. This means the stitching will be at the side of the tape.
- Trim any excess tape at the back.
Method #2 – Bias Bound Seams
- Sew your seam as normal and press the seam open or to the side.
- Press half-inch single fold bias tape in half.
- Slip the tape over the edge of the seam and pin.
- Stitch the bias tape in place. Make sure the machine catches each side of the tape.
Welt Closed Seams
The welt closed seam is a very easy flat seam. It is all stitched down making it seem enclosed but the raw edges are not exactly closed into the seam. The raw edges have to be neatened before the seam is constructed.
- Place the fabric right sides together.
- Sew your normal seam allowance.
- Press the seam open as you would for a normal open seam. Neaten the left side of the seam allowance with a zigzag, serger or pinking shears.
- Trim down the right side. Now you should have one side of the seam neatened and the other side trimmed.
- Press the seam allowances together so the neatened seam allowance is pressed over the trimmed side. This covers the trimmed side with a neatened piece and encloses it.
- Stitch along the neatened edge of the seam to sew the two pieces together. From the wrong side, you will see the neatened edge and a flat seam. On the right side, you will see a line of stitching.
Lapped Closed Seams
A lapped seam is just two pieces of fabric that overlap. It makes a very flat seam and cuts down on the bulk of thicker fabrics.
- Press over the raw edge of the top fabric.
- Overlap two pieces of fabric to be joined. Both pieces must have their right side facing up.
- Topstitch the one side of the lapped fabric, remember to stitch closely to the edge.
It really is a simple as that. You can take the lapped seam a step further and try a turned lap seam.
The Run and Fell Seam
This seam is completed on the right side of the fabric. It is a durable seam and ideal for clothing made of denim. Basically, the seam is stitched on the right side of the fabric and the one side of the seam is trimmed away and the other side overlaps to neaten the seam. One side is trimmed and the other folds over the trimmed edge and is topstitched in place. You will see run and fell seams used to sew denim. The run and fell seam is also known as a flat felled seam.
- Sew your pieces of fabric right sides together. Match sides and notches carefully. Use your given seam allowance or sew 1/2 inch from the edge.
- Press the seam open and trim 3/8 inch off one side of the seam allowance. Fold the remaining seam allowance over itself and press. This is the part that will cover the trimmed part of the seam.
- Fold the pressed part of the seam over the trimmed part and press again. This is the piece you are going to sew.
- Topstitch close to the edge about 1/16th along the folded edge to complete the seam.
- Press the seam on both sides and see how neat it looks on both sides of the fabric.
Closed Seams – In Conclusion
These different types of closed seams will open new doors to your sewing expertise. They add a seal of professionalism to your sewing and ensure your seams are strong, smart, and durable.