What Kinds of Fabric Shrink in the Dryer?

Shrink-Prone Fabrics

• Only fabrics made of natural fibers are subject to shrinkage when run through the dryer. Fabrics in this category commonly include cotton, wool and hemp. Natural raw denim will also shrink in the dryer, as will genuine leather garments and linen products. As a general rule, these types of fabrics shrink most heavily if they are completely composed of natural fibers; check the tag to find out about the contents of the fabric.

Cause

• Heat is commonly thought to be the culprit for dryer-based shrinkage. According to a 2005 report from Cotton Incorporated, however, this is not actually the case. The dryer's tumbling action actually causes clothes to shrink, as it causes moisture to evaporate from garments. In one study, Cotton Incorporated researchers found that a standard-sized load of 100 percent cotton fabrics shrinks about 20 percent when tumbled for 45 minutes.

Prevention

• To prevent shrinking your favorite clothes, step away from the dryer. Air drying does not cause fabrics, even natural fibers, to shrink at all; Don Bailey, Vice President of Textile Research and Implementation at Cotton Incorporated, says “cotton knits do not shrink when they are laid flat or hung to dry; yet, the same product shrinks when tumbled in the dryer.” At most, allow your clothes to tumble for only five minutes before hanging them out to air dry.

Shrink-Free Fabrics

• In contrast to fabrics made of natural fibers, fabrics made of synthetic or man-made materials generally do not shrink in the dryer. These fabrics include polyester, nylon and acrylic fabrics. Natural-synthetic blends, such as cotton-polyester blends, are less likely to shrink in the dryer than 100 percent natural fibers. Look for any labels that read “dry clean only” or “drip dry,” as these fabrics may shrink or fade from washing and drying. Closely woven fabrics tend to shrink less than loosely woven fabrics.