That’s a good question
What is the difference between single and double fold bias tape you ask?
Some people call it bias tape and others call it bias binding but they are both the same. If you are planning on doing some dressmaking or sewing then you will most probably need to use some bias binding at some point. Whether it’s to edge the neckline of a blouse or to finish a sleeveless armhole. Or even when working with applique. It can also be used as a pretty trim on the edges of pockets and used on the bottom of hems. So there are two types of bias tape. Single fold or double fold, and you may be wondering what is the difference between the two.
All bias tape starts out the same with a single strip of fabric that has been cut out on a 45° angle on the fabric. This angle is known as the true bias. Hence the name bias binding or bias tape. It has the most stretch to the fabric which is perfect for making into bias tape. It can then be manipulated around curves when sewing edges in dressmaking. In this post I am using purchased premade bias. I will cover how to make your own in another post.
Single Fold Bias Tape
Single fold bias tape is when the two long raw edges are folded into the centre of the tape. So that the final fabric strip width is half the original width. So for example, if your fabric strip is 2in then it will be become 1in single fold bias tape. See picture below …. how pretty is this! If you like this pretty tape we do have it stocked in our shop along with 6 other floral designs.
Double Fold Bias Tape
Similarly double fold bias tape is simply folding the single fold bias tape in half again. Thereby reducing the original strip down to a quarter. In the picture below you can see that the bias has been folded over on itself again and pinned in place. This is double fold.
So When Do You Use Them?
When I was Dressmaking recently I was making the Betty Blouse by Simply Sewing Magazine. I found it to be a really simple easy project to sew. All it needed was some bias tape on the neckline. The instructions required me to use double fold bias tape. See picture below.
Double Fold Method
So after choosing a pretty bias tape that coordinated with my fabric I attached the tape around the neckline using the double fold method.
By placing the double fold bias tape to the neckline, this meant I was sewing through 3 thicknesses. Once sewn in place I then turned the bias over to the wrong side and top stitched it in place.
Super easy and I think my preferred method.
Single Fold Method
If you were to add it using the single fold bias, you would open up the bias tape ….. see picture …
You would pin or clip your tape in place, sewing through the two layers. Then you would fold the tape over to the back and then sew in place with top stitch.
It all depends on what you are making and (if you are following pattern instructions) what is advised. Both methods give a very neat result and finish the edges of your projects perfectly.
So now you know the difference, you can go and create using both methods and be confident in using either the single fold or the double fold bias tape.