Pre-shrinking is treating fabric to remove its natural shrinkage before garments are cut - so the finished garment keeps its size after washing.
Why Fabrics Shrink
Weaving and knitting put yarns under tension, and that tension relaxes the first time fabric is washed - the fabric contracts. Natural fibers shrink most: untreated cotton knits can shrink 5-10%, wovens 2-5%. If garments are cut from unshrunk fabric, the customer's first wash ruins the fit.
Pre-Shrinking Methods
- Sanforizing - mechanical compression that pre-shrinks fabric (see our sanforizing guide)
- Steam shrinking - steam and pressure relax the fabric before cutting
- Wash/dry cycles - repeated laundering for knits, the most thorough but slowest method
What Happens Without It
Garments shrink after the first wash - the number one fit complaint in apparel. Sleeves shorten, bodies narrow, and customers return the product. Pre-shrinking is cheap insurance against the most common quality failure in clothing.
FAQs
- How much do fabrics shrink?
- Cotton knits 5-10% untreated; wovens 2-5%. Pre-shrinking brings residual shrinkage under 3%.
- Is pre-shrinking the same as sanforizing?
- Sanforizing is one mechanical method of pre-shrinking.
- Do synthetic fabrics need pre-shrinking?
- Less so - synthetics shrink minimally, but blends still benefit.
Glossary: see the full fashion glossary for more apparel industry terms.