Why Do Clothes Shrink in the Laundry?

Wool sweater on wooden surface next to woven basket and plastic bottle

The Spruce / Olivia Inman

Many of us are all too familiar with that sinking feeling of pulling our favorite clothing out of the dryer only to find it in a much smaller size than before. There's nothing worse than thinking you may have ruined your favorite sweater or work dress, and it can cause you to instantly think something may be up with your appliance. And, while the dryer may be to blame, there are actually quite a few other causes that can make your clothes shrink.

In fact, everything from the cycle we choose on the washing machine to the fabrics our clothes are made from can be to blame for this resize. If you want to avoid the constant tug of too-small clothes (or the need for a new wardrobe every season), consult these quick and easy tips for avoiding laundry shrinkage—plus all the reasons it may be happening in the first place.

Causes of Clothing Shrinkage

Generally, there are three different (and very technical) ways clothing can shrink: felting, relaxation, and consolidation. It may take a bit of time and training to learn which type of shrinkage is impacting your favorite pieces.

Felting Shrinkage

The first type of shrinkage, felting, occurs with clothing constructed of animal hair fibers, like wool or mohair. These materials have microscopic scales along their surface that, when exposed to moisture and excessive heat, can compress and mesh together. This compression is the cause of the all-too-familiar shrunken sweater syndrome, which can happen easily if the sweater is not handled correctly. This type of shrinkage is sometimes also referred to as progressive shrinkage because it will continue to happen a little more each time the animal hair fiber is washed.

Relaxation Shrinkage

Relaxation shrinkage happens when an absorbent fabric (like cotton, silk, or linen), or a fabric modified to be absorbent (like a synthetic performance fiber), is exposed to liquids or excessive moisture. When these absorbent fibers are exposed to water, they will soak it all up and swell, causing the overall size of the garment to shrink. Generally, relaxation shrinkage impacts less than one percent of the overall garment size and won't really influence a piece's fit.

Consolidation Shrinkage

Another common shrinkage issue is consolidation shrinkage, which occurs when moisture, heat, and mechanical action (like agitation during washing and drying cycles) are combined. The combination of these factors causes the fabric's fibers to release any pulling or tension put in place during the construction of the clothing item, which in turn relaxes the fibers, allowing them to return to their natural state (which is almost always smaller). Relaxation shrinkage typically occurs most dramatically during an item's first wash cycle and it can drastically reduce the size of a piece.

Prevention

When clothes shrink and stretch, many of the reasons as to why happen long before you get the piece home. However, there are ways you can help control shrinkage. One of the biggest: Follow the care labels on clothes. Sure, it's annoying to have to fish beneath your top to find out how to wash it, but those instructions are there for a reason. They're purposely designed with the garment's fibers in mind, so if the label tells you to skip hot water or only air dry, you should listen.

It's also a good idea to read any labels before you buy a piece, too. If you're shopping for an item made from natural fabrics like cotton, wool, or linen, pay special attention to any labels that mark the piece as "pre-shrunk." This means the fabric is shrunk before the garment is sewn together, so you can bet on less shrinkage during its time in your closet.

If you're unsure about how a fabric will react to its first wash, it's a good idea to opt for a cold rinse. While cold water won't prevent all shrinkage, it is definitely less damaging to fabric than hot water and can help ease your garment into washing. The same thing goes for drying your clothes, as well: Air drying a garment is often your best option, but if you can't do that, use the lowest heat setting on your drier.

Lastly, consider your washing and drying machines themselves. Any machine that is without a center agitator (the column that creates a "donut" shape in your washer) will be more gentle on clothes. If your machine does have a center agitator, reduce its impact on your garments by opting for a gentle or hand-wash cycle.

Definition

Shrinkage is defined as a change in the dimensions of a fabric or garment. The change may be negative (losing size from original measurements) or positive (growth in measurement) in the length, width, or thickness of the fabric or garment. While the thickness of a fabric can change over the course of the life of a garment, it does not usually cause a problem with the fit of a garment.

Shrinkage, whether a loss or addition of length or width dimensions, affects the fit of a garment. Shrinkage also can account for things like seam puckering, torquing (pull or hang of fabric), and decorative stitching distortion.