The One Thing You Don't Know About Sewing with Elastic

The One Thing You Probably Don’t Know About Sewing Elastic


I use a lot of elastic to make lingerie. I mean a lot. It is used for both the upper and lower edges of a bra, the legs and waist of underwear not to mention swimwear and active wear. It seems like I am always sewing with elastic!

I have talked about the types of elastic and its purpose before but there is one thing you need to do after sewing elastic thing that you probably don’t know about. Ready for this?! Steam it.

Let me explain. When you stretch elastic while you are sewing it, you are stretching it out of shape. You may not have realized this and even have tried on the garment thinking it was larger than you expected.

Think about wearing stretch jeans. After a couple of wearings, they feel loose. After you wash them, they are back to their original fitted state. You may notice the same thing with your bras. Which is one of the reasons why they require frequent washing.

To illustrate why elastic should be steamed after sewing, I put together a small sample (you can enlarge the images to see them more clearly):

  • 6” piece of power mesh that has 50% stretch in the direction of greatest stretch.
  • 4” piece of ⅜” wide elastic (the length in-between the markings on the elastic, from 1″ to 5″ on the ruler).

In this sample, the elastic is two-thirds of the length of the power mesh piece so it needs to be stretched to attach it to the swatch of power mesh.

Elastic and Power Mesh Swatches

Following is an image right after sewing the elastic onto the power mesh  using the classic two passes of zigzag stitches. Notice the piece is now 4 ¾” wide (from 1″ to 5 ¾” on the ruler, between the markings on the elastic).

Elastic Sewn to Power Mesh
After steaming here is the same swatch. It is now 4 ½” wide (from 1″ to 5 ½” on the ruler). The swatch ends up a bit longer than the original length of the elastic because the power mesh also has stretch.

Elastic and Power Mesh Steamed

You may be thinking that ¼” difference is not enough to bother with but for lingerie, even ⅛” makes a difference in the fit and feel of the garment. This is also a small swatch. This effect can be amplified depending on the fabric and length of the elasticized edge.

Now you know to give elastic a good steam after you finish sewing it to restore it to its neutral state. Just be sure to only use steam on elastic. Never directly iron or press elastic or you will get a melty mess!