What is Stretch Factor?
Posted on 09 July 2018
Not all stretch fabrics are the same.
They vary in several ways including how they sit around the body, how they stretch around the body & their drape.
Both fabric content & stretch factor play an important role in this.
Each fabric’s stretch factor plays a big part in this, as does their lycra, spandex or elastane content. Below is a guide to help you choose your fabric.
In the handmade world, stretch knit fabric is generally described as either 2-way or 4-way stretch.
WHAT IS 4-WAY STRETCH FABRIC?
- The fabric stretches both across the fabric AND up & down the fabric.
- Generally recovers much better than a 2-way stretch.
- Contains a % of lycra, spandex or elastane to give it that stretch & recovery.
- Perfect for fitted or fit & flare stretch garments that need to stretch over our curves.
- Recommended for the Spellbound & Wanderlust Dresses, the True Romance, Allure & Trapeze Tops.
- Recommended for the waistband of the Heartlight & Starlight Skirts.
WHAT IS 2-WAY STRETCH FABRIC?
- Fabric stretches selvage to selvage, horizontally across the fabric BUT NOT vertically up and down the fabric.
- Not suitable for fitted stretch garments when the vertical stretch is zero (rigid).
NOTE: You will sometimes find fabrics that have a reasonable amount of vertical stretch (give/slight stretch), despite being described as a 2 way stretch. Do a stretch factor test (outlined below) if you can and if buying online, ask the seller if there is any vertical give.
WHAT IS A FABRIC'S STRETCH FACTOR?
Stretch factor is how far a fabric stretches past it’s relaxed state. This is important for the correct fit of a stretch fitted garment.
WHY IS STRETCH FACTOR IMPORTANT?
If you are sewing a fitted stretch garment it's important for the fabric to have both horizontal & vertical stretch.
As a fabric stretches OUT on your body, it will also pull UP.
For this reason, it's important for a fitted stretch garment to be made out of 4-way stretch.
If a fabric has no vertical stretch, the fabric won't be able to comfortably pull up, making it too short both through the body, crotch, armhole &/or legs. This can be very uncomfortable.
HOW TO DETERMINE STRETCH FABRIC:
Determining stretch fabric is super easy. Here's how:
1. PRINT OUT THE STRETCH FACTOR GUIDE:
- Print out this simple stretch guide first. Click here to download the pdf.
- Make sure it's printed actual size. Do not scale.
2. CUT AND LABEL A FABRIC SWATCH:
- Measure & cut a fabric sample 10cm x 10cm (3 7/8”), on the grain of the fabric.
- Don’t include the actual selvage in your sample.
- Draw an arrow on your fabric to remind you which direction horizontal is.
3. DETERMINE HORIZONTAL STRETCH
- Fold the fabric swatch in half, along the horizontal grain.
- Hold fabric at left edge (A) of guide & stretch as far right as possible.
- Note the % stretch factor it reaches on the guide.
4. VERTICAL STRETCH
- Repeat Steps 3-5, this time folding the fabric in half along the vertical grain.
WHAT STRETCH FACTOR DO I NEED TO SEW PATTERN EMPORIUM PATTERNS?
Simply refer to the fabric pages of your Pattern Emporium pattern. It will tell you exactly what stretch fabric you need.
WHAT FABRICS HAVE 4-WAY STRETCH?
ITY, cotton elastane, poly elastane, poly jersey, swimwear fabric, some pontes, rayon elastane, rayon bamboo elastane, stretch lace, stretch velour (stretch velvet), double brushed polyester.
Note: swimwear & leggings fabrics may fit firmer than other fabrics due to the nature of the stretch.
PATTERN EMPORIUM STRETCH PATTERNS
To view our collection of stretch patterns, click here.
These include skirts, tops & dresses.