Flat felled seams are simple but effective. They are overlapped seams that provide extra strength and durability but also sit nice and flat so reducing any bulk. They can usually be found on tailored shirts or trousers where there can be quite a bit of strain placed on the seam but it still needs to lay flat against the body. Jeans are a good example of this.
We have also used them in our Beatrice Pinafore and the Infinity Scarf as this particular seam encloses all the raw edges to keep things nice and neatly finished.
There are several different ways to create a flat felled seam but I have found this to be the simplest.
Place the fabrics with the right sides together and sew a normal 1.5cm or 5/8” seam. Press the seam flat as it’s been sewn and then trim down one side of the seam allowance to just 6mm or 1/4″.
Fold the other side of the seam allowance down over the trimmed one so the raw edge sits along the sewing line. Press this in place.
Fold the whole seam over along the stitching line so all of the raw edges are underneath the seam.
Edge stitch down the seam allowance.
So you will have a double row of stitching on the wrong side and a single row on the right side of the garment.
This is a very easy seam to achieve with out the need for specialist machine feet. Why not give it a go!