A bias binding (also known as a bound edge or edge binding) is one of those assets which many people who make their own drapes don't use. This a is great pity, because it's easy to do and gives a great finish to drapery elements.
It's useful for items such as bedspreads and tablecloths, as well as swags, cascades (tails) and valances. It's particularly effective when a contrasting fabric is used.
You'll often have plain fabric left over from other jobs you've done, and if you have enough and it's a suitable color it can be used for bound edges.
There are two simple rules to remember.
If you're applying a bias binding to any straight edge, cut the fabric for the binding on the straight grain, vertically or horizontally.
For a curved edge, cut the fabric on the true cross (45 degrees to the selvage). Obviously these can only be a certain length, depending on the width of the fabric. Longer lengths are made by joining strips at right angles.
For most situations keep your bias binding narrow, about ¾ inches (2.0cms). When cutting for side edges, such as a drape panel, cut strips as long as the cut length of the drape so there are no joins.
For top and base edges, cut the number of strips to match the number of widths for the item in question. So if the binding is for the top edge of a valance which consists of four widths, cut four strips so the joins will match the joins of the valance.
For all trims, the width of the fabric will be 4 times the binding width.
Note: If you bind an edge on a treatment you can leave the raw edges because the binding will cover them. So for example, if you're making a swag, you don't need to hand sew the edges neatly. You could simply machine them together and use the binding to cover the join.
The illustration shows how to attach the bias binding to the edge of an item consisting of a main fabric and lining (you could include interlining as well). You could machine sew all the layers of fabric at the same time, or apply the binding after the others have been sewn together.
Make sure you sew the reverse side of the trim onto the front of the main fabric, so the correct side of the trim is visible when it is turned over to the back.
When the trim is in place, fold it over to the back, and fold the turning under (see previous illustration) so it mirrors the turning on the front.
For a neat finish, fold the turning under so it just covers the machined seam. Pin it in position, and hand slip stitch to finish off.
Bias binding edges are a very useful addition to your drapery making options. They are easy to make, and give a great finish to your projects