You don’t have to be an experienced sewist to finish your knitted garment with a zip. With careful preparation, you’ll have a professional finish in no time!
Choosing the right zip
First consider the weight of your yarn and choose a zip accordingly. If you can, try to find a zip of a similar weight to (or something slightly lighter than) the knitted fabric. The teeth will add a stiffness to the fabric and help to stabilise the edge, so it’s important that you don’t choose something too heavy, particularly if your fabric is on the finer side.
Zips are available in many different sizes with either plastic or metal teeth. Larger teeth work well with knitted fabric, and choosing something with smooth teeth will help to ensure that the knitted stitches don’t get caught.
Your chosen zip should be exactly the same length as your garment’s front bands when the zip is closed. If the zip is longer, the front won’t hang straight, while if the zip is shorter you’ll be left with a gap at the top or bottom - so take care to measure your project correctly before you head to the haberdashery!
Before you begin
You’d usually sew a zip into the completed garment, so do any sewing up and finishing that needs to be done. Wash and block the garment carefully, including any pre-shrinking that may be required, and ensure the garment is completely dry before starting.
When blocking, make sure both sides of the knitting you want to sew the zip into are the same length. This is important, as once the zip is sewn in there won’t be any give in this edge if it needs any adjustment. Finally, choose a thread that matches the yarn, rather than the zip, if there is a difference between the two. We’ve chosen a contrast colour for our photos so that our sewn stitches will show up.
Pinning the first side
With the zip closed, you’ll pin one side at a time, making sure that neither the fabric or the zip are pulled unnaturally and are laying flat and relaxed. You may find it helpful to place a piece of card or thick paper between the front and back of the garment to prevent pinning the two sides together and to help keep edges flat.
Set the fabric edges alongside the teeth, making sure there is space for the zip to run without the teeth catching on stitches. It might sound obvious, but you’ll want the top of the front band to be level with the stopper at the top of the zip, and the bottom of the band to be even with the bottom of the zip.
Place pins at the top and bottom first, facing in towards the zip.
Pin the centre of the zip with the band on both sides, then work in sections, pinning between the pins until the remainder of the zip is pinned in place.
Note: we’ve used a suggested stitch length here of 5mm; however, the length of the stitches can be adjusted depending on the weight of the yarn used, or you may prefer to use the knitted stitches as a guide. For best results, follow a column of stitches as you work up the zip for a straight edge.
When sewing, always go though the fabric by going straight up and down, and work one stitch at a time rather than using a running stitch as it may cause the fabric to bunch up.
Thread the needle and knot the end.
Beginning at the bottom of the zip, insert needle from the wrong side to the right side, pull through, and insert the needle back through the zip and the fabric, about 5mm in front of where you came up, to complete the first stitch.
Push the needle back into the fabricand the zip, about 5mm in front of the last stitch, then push the needle back through at the place the last st ends.
Repeat step 3 along the zip.
Pinning the second side
Pin the second side in the same way, making sure to match any stripes or patterns as you go, beginning at the bottom and working in the same direction to ensure that the bottom of the zip will meet neatly when it’s closed.
Turn the project inside out so that the wrong side is facing.
Fold the fabric part of the zip back towards the WS on a diagonal and stitch in place.
Work a slip stitch along the outside edge of the zip to keep it laying flat. Don’t pull the thread too tight.
The finished zip, viewed from the WS.
About our expert
Faye Perriam-Reed is a designer and the technical editor of The Knitter and Simply Knitting. She enjoys exploring construction and finishing techniques to achieve neater results.