How To Prewash Fabrics And Why To Do So

How frequently should I prewash my fabrics? What does prewashing entail? Is it essential or even beneficial?

Prewashing refers to washing fabric before sewing it. This helps remove unwanted chemicals from the fabric and makes sewing easier. However, you don’t want to wash your fabrics too frequently because they tend to shrink after each wash. If you’re using cotton, linen, silk, wool, rayon, or other delicate fabrics, you might consider prewashing them once every two weeks.

Prewashing is important because it removes excess chemicals from the fabric. These chemicals build up over time and cause problems such as fading, shrinking, and pilling. The good thing about prewashing is that it reduces static electricity, which means less fuzziness during sewing.

Key Takeaways

  • Pre-washing fabric is essential for shrinking and cleaning.
    • Natural fibers often shrink, so pre-washing prevents misfit garments.
    • Pre-washing removes dirt, chemicals, and excess dye from production, softening the fabric.
  • Not all fabrics require pre-washing.
    • Accessories that won’t be machine washed or dry cleaned, only items like woolen jackets, should not be pre-washed. Instead, steam can be used to pre-shrink these fabrics.
  • Synthetic fabrics may not need pre-washing for shrinkage, but cleaning them can be beneficial.
  • Preventing fabric from fraying during pre-washing is important.
    • Techniques include using a serger, zigzag stitching, fabric tube creation, pinking shears, or pre-fraying edges.
  • Additional tips for pre-washing include:
    • Wash a test swatch to measure shrinkage.
    • Unfold the fabric fully before washing.
    • Avoid overloading the washing machine.
    • Wash similar colors together to prevent dye transfer.
    • Ironing and cataloging pre-washed fabric is recommended for an organization.

What Are The Main Reasons Why You Should Pre-Wash Your Fabric?

Prewashing fabrics is a very common practice nowadays. Many sewers do it because they want their projects to look neat and clean after finishing. However, if you don’t prewash your fabric, you might get unwanted stains or shrinkage.

There are several reasons why you should prewash your fabric:

  • For pre-shrinking.
  • During the production process, dirt and chemicals must be washed out.
  • Washing natural fiber fabrics shrinks them most of the time. Cotton fabrics’ shrinkage rate is usually around 5%, while fabrics made from natural fibers can shrink up to 10%. Your final garment might not fit correctly if you didn’t wash your fabric before sewing.

The fabric should be washed and dried just like the final garment to prevent this. Give the fabric a hand wash if you plan on handwashing it. You can wash it in the machine at 30 °C if you plan to.

Wearing a garment reduces shrinkage (like after washing jeans) but not lengthwise shrinkage. Prewashing is worth the effort if the garment is fitted or if fit and size are important.

The production process must also be washed out to remove dirt, chemical sizing, starch treatments, and excess dye. In addition to making the fabric easier to handle during production and strengthening the yarn for weaving, the treatments soften the fabric when washed out.

When Should You Not Prewash Fabric?

For example, if I were to sew a zippered pouch or shoulder bag that would only be spot-cleaned, it wouldn’t be washable in a washing machine.

These fabrics must be dry cleaned, and garments must be more structured, such as woolen and tailored jackets. If this is the case, I steam the fabric using an iron hovered above it (not directly on it!). Steam also assists in pre-shrinking the fabric.

Some people do not prewash denim because white lines may appear on their denim fabric after prewashing raw indigo denim.

If you want to work with a clean fabric, you might still want to prewash 100 percent synthetic fabrics to prevent shrinkage.

How To Pre-Wash Fabric?

If you don’t treat your raw fabric edges first, you might lose some of your lengths if you wash and dry your fabric as you would your finished garment, but we already mentioned you should wash and dry your fabric as you would wash and dry the finished garment.

How Can You Prevent Your Fabric From Fraying When You Prewash It?

It is the cut ends that fray, not the hem. Fraying can be prevented and reduced in a few ways:

  • Finish the edges of the fabric with a serger.
  • The edge of the fabric should be stitched with a zigzag stitch.
  • The cut ends should be zigzagged or serged together to create a tube.
  • Pinking shears help reduce fraying. Fabrics with a finer weave that do not easily fray are the best to use this method on.
  • Prepare your fabric by fraying it beforehand. In linen placemats and scarf ends, you see this frayed edge that prevents further fraying by pulling out the weft thread about a cm or 3/8″.
  • Don’t…let it fray. Let it fray, and cut off the fraying edge after it dries.

We pre-frayed the edges to look decorative and prevent further fraying for the cotton muslin rectangles we used to print on. Our silky woven bamboo viscose is an absolute tangled nightmare if you throw it in the washing machine.

The Best Way To Pre-wash Your Fabric

  • Make a test swatch and wash it. After washing, you can measure the size of a square cut at 10 cm or 4 inches. If you finish the edges before washing, you can see how much the fabric shrinks and how well it holds up.
  • Make sure your fabric is unfolded before you put it in the washer.
  • Washing machines shouldn’t be overcrowded.
  • If the new fabric contains excess dye, it might be necessary to wash similar colors together to prevent stains from occurring on other fabrics.
  • Your fabric swatch library will be enhanced if you iron your pre-washed fabric immediately.

Generally, it’s recommended to pre-wash fabric for most garments, but it does depend on the fabric and the project. If you are unsure, ask the shop where you bought the fabric for tips and wash a test swatch first.

What Does Pre-Washing Fabric Mean?

Pre-washing fabric means washing your clothes before wearing them. This helps remove dirt from the clothing, making it easier to wear. If you do not prewash your clothes, they may become dirty after just one use.

Should You Pre-Wash the Fabric Before Sewing?

Yes! You’ll get a better result if you pre-wash the fabric before sewing. The best way to prewash fabric is to put it into a washing machine with cold water and spin it for 10 minutes. After spinning, hang up the washed fabric to dry. This process helps remove any dirt from the fabric, which makes it easier to sew.

Do you use soap when pre-washing fabric?

Prewashing your fabric in a washing machine is probably fine if you are using detergent. Do not use too much, however. According to many sewists, use half the amount you usually would.

What Is Pre-Wash Cotton?

Pre-wash cotton is a type of fabric that was washed before dying. This process removes dirt, stains, and other impurities from the fabric, making it perfect for clothing, bedding, towels, and home decor.

What Happens If You Don’t Pre-Wash Fabric?

The best way to wash fabric is to prewash it first. This process removes any dirt from the fabric, which helps prevent stains. However, some fabrics cannot be prewashed. Cotton, for example, needs to be washed separately.

Why Does Fabric Say Do Not Prewash?

The fabric industry has been using do not prewash for decades. This is because the chemicals used in the process cause the fabrics to shrink and lose strength. If you want to wash your clothes, use cold water and hang them to dry.

How Do You Prewash Fabric Without Fraying?

To prewash fabric without fraying, use a dryer sheet. The dryer sheets contain chemicals that help prevent static cling from building up on clothes. They also absorb moisture and odors. If you don’t want dryer sheets, try using a damp cloth.

How Do You Prepare Fabric Before Sewing?

When preparing fabric for sewing, the first step is to wash it thoroughly. This removes any dirt or stains. Next, iron out all wrinkles using an iron set at high heat. Finally, cut the fabric into pieces according to the pattern instructions.

Do I Need To Pre-Wash Polyester Fabric?

If you want to wash the polyester fabric, prewash it first. The purpose of washing polyester fabric is to remove dirt from its surface. This process removes stains and helps prevent them from reappearing later. However, if you don’t do this step, the stain may return when you rewash the item.

How To Pre-Wash Jersey Fabric?

If you want to wash the fabric, prewash it first. Washing removes dirt from the fabric’s surface, stains, and other impurities. It also helps prevent shrinkage, meaning the fabric shrinks less when washed.

How To Pre-wash Fabric By Hand?

The best way to pre-wash fabric by hand is to use cold water and soap. This method works well for delicate fabrics such as silk, wool, and cotton. However, washing machine washes work better for heavier fabrics like denim and flannel.

How to Pre-Wash Fabric

Handling Different Fabric Types

Sewing Natural Fibers

Fabrics made from natural fibers should be washed and dried in the same manner as the finished garment will be cared for. This could mean machine washing on a gentle cycle for cotton or hand washing for delicate silks.

Synthetic Fabrics

While synthetic fabrics like polyester may not shrink, pre-washing them can remove surface finishes and ensure the fabric is clean before sewing.

Preventing Fraying

Unfinished fabric edges can fray during washing, potentially causing material loss. Techniques such as serging, zig-zag stitching, or using pinking shears can help prevent fraying. For fabrics prone to significant fraying, creating a temporary seam or using fray-preventative products may be necessary.

Washing Techniques

  • Lukewarm Water Washing: Use lukewarm water for most fabrics to prevent excessive shrinkage or color loss.
  • Mild Detergent Use: Choose a mild detergent to protect fabric fibers and colors.
  • Drying Fabric Properly: Follow the care label instructions for drying. Some fabrics may be better suited to air drying to prevent shrinkage or fabric damage.

How To Prewash Fabrics FAQs

Should I pre-wash fabric for every sewing project?

It’s advisable to pre-wash fabric for garments or items that will be washed after construction. Exceptions include projects where the fabric will only be spot-cleaned or dry-cleaned.

Can I prevent the fabric from shrinking altogether?

While pre-washing minimizes initial shrinkage, natural fibers may experience minor shrinkage over time. For the best results, always follow care labels.

How do I handle pre-washing large amounts of fabric?

Consider washing in sections or using commercial laundry facilities for large volumes. Ensure the fabric is fully unfolded and not overcrowded in the washer.

Pre-washing fabric before sewing is essential in preparing and ensuring your projects remain beautiful and functional. By understanding the reasons for pre-washing and employing the correct techniques, you can achieve professional-quality results in your sewing endeavors.


In conclusion, there are many benefits to prewashing your fabrics before you begin your sewing project. Prewashing fabrics can remove any unwanted chemicals, sizing, or finishes that may be present on the fabric. It can also help to shrink the fabric so it doesn’t become too big for your project. Prewashing can also help to set the colors in the fabric so that they don’t bleed when you wash your finished project.

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