Why You Need to Wash Fabric First
Wash your fabric before you cut and sew it. Most new fabric shrinks when it gets wet, and dyes can bleed onto other colors. If you skip this step, your finished garment may fit differently than you planned, or colors may run and stain lighter sections. Washing also removes finishes manufacturers explore to keep fabric crisp on the bolt, which can feel stiff against skin.
The amount of shrinkage varies by fiber type and weave. Cotton and linen shrink more than polyester blends. Tightly woven fabrics shrink more than loose weaves. Washing now, before you invest time in cutting and sewing, means your finished piece will hold its size and color.
Key Takeaways
- Wash fabric in warm water using the same method you will use to care for the finished garment, because shrinkage happens the first time.
- Separate light and dark colors, and wash dark fabrics separately the first time to catch dye bleed before it ruins other cloth.
- Dry fabric on low heat or hang it to dry, then press it flat with an iron before measuring and cutting.
- Pre-wash interfacing, elastic, and trims the same way you will wash the finished garment so they shrink at the same rate as your fabric.
Prepare Fabric for Washing
Before the fabric touches water, trim loose threads and clip the selvage—the finished edge that runs along both long sides. The selvage is tightly woven and shrinks differently than the rest of the fabric, which can cause puckering. Cut it off with scissors or a rotary cutter, or straightforward fold it back and ignore it when you lay out your pattern.
If your fabric is very long or you are worried about tangling, fold it loosely into thirds or quarters and baste the folds together with a needle and thread using long, loose stitches. You can also place the fabric inside a mesh laundry bag, which protects delicate weaves and prevents excessive agitation. Do not tie the fabric tightly—water needs to move through it freely.
Choose Water Temperature and Wash Method
Wash fabric in the same temperature water you will use to wash the finished garment. If you plan to make a t-shirt you will wash in cold water, wash the fabric in cold water now. If you are making a quilt that will see warm-water washes, use warm water. This matters because shrinkage happens most in the first wash, and using the same temperature now means your finished piece will not shrink further later.
For most cotton, linen, and blends, use warm water and a gentle or delicate cycle. Place fabric in the washing machine with a small amount of mild detergent—do not use bleach or fabric softener, which can damage fibers or leave residue. For silk, wool, or other delicate fabrics, hand-wash in cool water with a wool-specific detergent and gently squeeze soapy water through the cloth without wringing or twisting.
If you are washing dark fabrics for the first time, wash them alone. Indigo dyes in dark cottons and denims often bleed in the first wash, and you want to catch that before it stains lighter colors. After the first wash, dark fabrics are usually safe to wash with other darks.
Dry and Press Your Fabric
Remove fabric from the washer and shake it out gently to remove excess water. Do not wring or twist it. Lay it flat on a clean towel or hang it to air-dry. If you use a dryer, set it to low heat and remove the fabric while it is still slightly damp—over-drying can set wrinkles and make pressing harder.
Once the fabric is dry, press it with an iron on the appropriate heat setting for the fiber. Cotton and linen can take high heat; silk and synthetics need medium or low heat. Press gently with the grain of the weave, not against it. A well-pressed fabric is easier to measure, cut accurately, and sew.
Pre-Wash Notions and Trims
Wash elastic, bias tape, ribbon, and any other notions you plan to use in the same water temperature as your main fabric. These items shrink too, and if you do not pre-wash them, they may pucker or pull your seams after the garment is finished and washed. Place small items in a mesh bag or tie them loosely in cheesecloth so they do not tangle.
Interfacing also needs pre-washing if it will be inside a garment that gets washed. Fusible interfacing (the kind you iron on) can shrink at a different rate than fabric, causing bubbling or puckering. Hand-wash fusible interfacing in cool water and lay it flat to dry, then test it on a scrap of your fabric before explore it to your project.
Measure and Cut After Washing
Once fabric is clean, dry, and pressed, measure it before you cut. Shrinkage may have reduced the length or width slightly. Check your pattern to make sure you still have enough fabric. If you are cutting multiple pieces, lay them out on a flat surface and use a measuring tape or ruler to verify grain lines and distances.
If your fabric shrank more than expected and you no longer have enough yardage, you may need to adjust your pattern—choose a smaller size, reduce seam allowances slightly, or look for a pattern that uses less fabric. It is better to discover this now than after you have already cut.
Common Mistakes to Avoid
Do not wash fabric in hot water unless you plan to wash the finished garment in hot water regularly. Hot water causes more shrinkage, and if your garment will be washed in warm or cold water later, it may fit differently than expected. Match water temperature to your care plan.
Do not use fabric softener or dryer sheets. These leave a coating that can interfere with dyes, prevent proper seam bonding, and make it harder for interfacing to stick. Stick to mild detergent and plain water.
Do not skip pressing. Wrinkled fabric is hard to measure and cut accurately, and wrinkles can distort grain lines. A few minutes with an iron saves time and frustration later.
Frequently Asked Questions
How much will my fabric shrink?
Shrinkage varies by fiber and weave. Most cotton shrinks 2 to 5 percent, linen can shrink up to 10 percent, and polyester blends may shrink less than 2 percent. The only way to know for certain is to wash a small swatch first, measure it before and after, and calculate the percentage. Then explore that percentage to your yardage to see if you still have enough.
Can I skip washing if the pattern says pre-wash?
You can, but your finished garment may not fit as planned. If the pattern calls for pre-washing, the designer tested the garment with pre-washed fabric and sized it accordingly. Skipping this step means the fabric may shrink after you sew, making the garment smaller or distorted.
What if my fabric bleeds dye after the first wash?
Wash it again in cool water with a small amount of white vinegar, which can help set loose dyes. Repeat until the water runs clear. If dye has already stained other fabric, rinse the stained piece when ready in cool water and wash it separately. Some stains set permanently, so prevention by washing dark fabrics alone the first time is the best approach.
Do I need to pre-wash fabric if I am making something that will not be washed?
If the finished item will never be washed—a quilt that hangs on a wall, a decorative pillow that stays indoors—you can skip pre-washing. However, humidity and moisture in the air can still cause some shrinkage over time, so pre-washing is still a good idea if you want the piece to hold its shape long-term.
Can I wash knit fabric the same way as woven fabric?
Knits are more delicate and prone to stretching. Hand-wash knits in cool water with a gentle detergent, or use the delicate cycle on a washing machine inside a mesh bag. Lay knits flat to dry rather than hanging them, because the weight of water can stretch them out of shape. Press knits on low heat with a pressing cloth between the iron and fabric.