Sewing with Spandex: What to Know Before You Start

Spandex can feel intimidating at first, but it is also one of the most forgiving fabrics once you learn a few simple tricks. Because it stretches and moves with the body, spandex opens up a whole world of sewing possibilities: leggings, T-shirts, headbands, dancewear, swimwear, costumes, pajamas, activewear, and more.

The best part? Stretch fabrics can be a little more forgiving with fit than woven fabrics, which makes them a great choice for comfortable clothing.

What Is Spandex?

Spandex, also called elastane, is a synthetic fiber that gives fabric stretch and recovery. It can stretch several times its original length, but it is rarely used by itself. Instead, spandex is blended with other fibers to create fabrics with different levels of stretch, softness, durability, and drape.

You may also see the name Lycra. Lycra is a brand name for spandex/elastane.

Common Spandex Blends

Cotton Spandex

Cotton spandex is soft, breathable, and comfortable. It is a great choice for everyday projects like T-shirts, leggings, headbands, baby clothes, and casual dresses.

This is one of the friendlier spandex fabrics to start with because it usually is not too slippery.

Polyester Spandex

Polyester spandex has a smoother feel and is usually more durable than cotton spandex. It tends to hold up well to wear, which makes it a popular choice for athletic wear, dance uniforms, costumes, and some swimwear.

Nylon Spandex

Nylon spandex is the luxury option in the spandex world. It is soft, smooth, strong, and has excellent stretch. It is commonly used for swimwear, activewear, shapewear, bras, and dancewear.

Rayon or Bamboo Spandex

Rayon and bamboo blends are often the softest and drapiest spandex fabrics. They feel wonderful for tops, dresses, pajamas, and lounge clothes.

The trade off is that they can be more prone to pilling and may not be the best choice for high friction projects like activewear or leggings.

2-Way Stretch vs. 4-Way Stretch

When sewing with spandex, always check your pattern’s fabric requirements. Some patterns ask for 2-way stretch, while others ask for 4-way stretch.

2-way stretch means the fabric stretches side to side, usually from selvage to selvage. This gives stretch around the body while still offering support in the other direction.

4-way stretch means the fabric stretches both side to side and up and down. This is helpful for garments that need more movement, such as leggings, swimwear, dancewear, athletic wear, and fitted clothing.

If your pattern calls for 4-way stretch, do not substitute a 2-way stretch fabric unless you are very confident it will still work for the garment.

What Is Degree of Stretch?

Your pattern may also list a required degree of stretch, sometimes written as DOS or stretch percentage.

This tells you how much the fabric needs to stretch for the garment to fit and move properly.

Here is an easy way to test it:

1. Mark a 4" section of fabric.
2. Hold one end in place.
3. Gently stretch the other end.
4. See how far it stretches without forcing it.

If your 4" section stretches to 6", that is 50% stretch.

If your 4" section stretches to 8", that is 100% stretch.

The fabric does not need to be stretched until it is struggling. You want to know how far it stretches comfortably.

Don’t Forget Stretch Recovery

Stretch is only part of the story. You also want to check the fabric’s recovery.

Recovery means how well the fabric returns to its original shape after being stretched. A fabric with good recovery will snap back nicely. A fabric with poor recovery may stay stretched out, ripple, or look loose after being pulled.

This matters because poor recovery can lead to baggy knees, stretched out necklines, wavy waistbands, or garments that look great when first sewn but lose their shape after wearing.

Before starting your project, stretch the fabric and let it go. If it returns to its original shape, that is a good sign. If it stays stretched out, you may want to choose a different fabric or use it for a looser fitting project.

What Needle Should You Use?

When sewing spandex, a stretch needle is usually the best choice.

A stretch needle is similar to a ballpoint needle, but it is designed to work better with elastic fabrics. It helps prevent skipped stitches, puckering, bubbling, and pulls in the fabric.

For many spandex fabrics, start with a stretch needle in size 75/11 or 80/12.

Do You Need a Serger?

No, you do not need a serger to sew spandex.

A serger is helpful because it trims the edge, finishes the seam, and creates a stretchy seam all at once. It gives the inside of the garment a clean, professional finish.

But you can absolutely sew spandex on a regular sewing machine.

On a sewing machine, use a stitch that can stretch, such as:

• Narrow zigzag stitch
• Lightning stitch
• Stretch stitch

These stitches allow the seam to move with the fabric instead of popping when the garment stretches.

What About Thread?

All purpose polyester thread works well for many spandex projects.

For extra stretch, especially when using a serger, woolly nylon thread can be used in the loopers. This gives the seam more softness and stretch.

Another option is Mettler Seraflex, an elastic sewing thread that allows you to sew stretch fabrics with a straight stitch while still keeping stretch in the seam. This can be helpful when you want a smoother looking seam on a regular sewing machine.

How to Prevent Wavy Seams

If your fabric starts waving or rippling while you sew, don’t panic. This is common with stretchy fabrics.

Usually, it means the fabric is being stretched as it goes through the machine.

Try these fixes:

• Lower the presser foot pressure if your machine allows it.
• Do not pull the fabric while sewing.
• Let the feed dogs move the fabric.
• Use a walking foot if needed.
• If using a serger, adjust the differential feed.

A lighter presser foot pressure helps the fabric glide through the machine instead of being pushed and stretched out.

Final Thoughts

Spandex may look intimidating on the bolt, but it is not something to be afraid of. The key is to check your pattern requirements, test the stretch, use the right needle, and choose a stitch that can move with the fabric.

Start with a simple project, test on scraps, and give yourself permission to practice. Once you get comfortable with spandex, you may find that it becomes one of your favorite fabrics to sew.

Stretch fabric means comfortable clothes, better movement, and a lot more creative possibilities — and that is worth learning.