Have you ever stared at the wet laundry in your washing machine and wondered which garments should go in the dryer? You probably know that every kind of fabric reacts differently to heat. For example, does polyester shrink in the washer or dryer?
Polyester does not shrink in a warm washing machine cycle, and it can safely go in a normal dryer setting as well. However, soaking polyester in hot water or leaving it in the dryer for an extended period may cause the fabric to shrink or warp. Polyester blends shrink more easily than 100% polyester.
Let’s take a look at what happens to polyester in the wash, how to care for this fabric, and how to shrink it on purpose.
Does 100% Polyester Shrink?
It is difficult to shrink 100% polyester. While you can melt this fabric at a high enough temperature, the polymer fibers are designed specifically for their strength and durability and can withstand pretty tough circumstances without stretching or shrinking. On top of that, special chemical treatments give many polyester garments extra protection against shrinkage.
Polyester fabric is essentially plastic; it’s a synthetic fabric made with long, durable yarns. Its fibers begin life as a chemical reaction between an alcohol and an acid, have a brief life cycle as brittle shards of plastic, and then become molten plastic melted and spun out into tiny threads. These lab-designed fibers can withstand a lot without getting damaged.
So, as long as you keep polyester away from very high heat, it will pretty much last forever! Normal washing and drying settings should never damage a 100% polyester garment.
You could probably throw a 100% polyester shirt into the Mississippi river way up in Minnesota, watch it tumble its way through 31 states, and then fish it out of the Gulf of Mexico pretty much undamaged. (Please don’t dump your shirt into a body of water, though! It would damage the local environment, even if the polyester itself remained untouched!).
All that said, you can destroy any fabric, even a synthetic polyester if you do not take the proper steps to care for it. It’s not easy, but you can melt, shrink, or misshape polyester by exposing it to temperatures that warp or melt those tough little fibers.
So, what does actually shrink polyester? There’s a very simple answer: high heat.
We’re not talking about sitting in the stands at your daughter’s soccer practice in ninety-degree weather kind of heat. However, ironing may scorch or melt the fabric. Submersing polyester in boiling water will cause its fibers to constrict and shrink.
This holds true for most kinds of fabric. Fabric fibers are spun and stretched out into threads before being woven into cloth. High heat releases this tension and allows the fibers to snap back into their shorter, original length.
Polyester holds out better than many natural fabrics in this regard. While it’s easy to accidentally scorch polyester with an iron, it’s quite tricky to make it shrink. We’ll look at tips for shrinking polyester on purpose later on!
Does Polyester Shrink In the Washer?
While polyester does not shrink in cool or warm washing machine cycles, washing it in hot water can cause a tiny amount of shrinking. If you want to take extra precautions, you should set your washing machine to permanent press and use cool water. This will save your hot water bill, too!
To avoid causing any shrinking, you should never wash polyester in temperatures above 230℉.
As you’ll see in a moment, many polyester blends require more delicate care than 100% polyester. It’s always key to check the care label in a garment to determine what kind of fabric it is made of and how best to care for it before throwing it in the washer.
How to Wash Polyester Fabric
Here are some quick tips for washing polyester.
- Turn your garments inside out to avoid any snagging on zippers and other sharp objects. Turning a polyester garment inside out also protects its coloring and prevents fading.
- Use cold or warm water settings on your washing machine.
- For best results, set your machine to permanent press–this setting uses slower spin cycles that causes less friction rubbing on your garments and prevents wrinkling.
- Regular laundry detergent works just fine, though a gentler option won’t hurt!
Does Polyester Shrink In the Dryer?
Polyester does not shrink in a normal dryer cycle. With the caveat that you should always follow the directions on the care tag of any individual garment, most of the time, it is perfectly safe to run polyester through normal dryer settings.
If your dryer has multiple heat settings, use the lowest setting. Your owner’s manual will provide details about dryer settings. You will want to make sure that you do not expose polyester to temperatures above and 100℉ in the dryer.
What causes clothes to shrink in the dryer? Dryers use motion and heat to dry clothes quickly. Heat causes fabric fibers to constrict, as mentioned earlier.
Some fabrics react dramatically to even low heat settings and should never go in the dryer. One-hundred-percent polyester, on the other hand, will shrink only if you turn up your dryer to its highest heat setting, if you run the garment through multiple dryer cycles, or if you wash the garment in boiling water and then place it in the dryer.
Normal dryer settings should not cause any damage to your clothing. For the best results, though, you could take a few special steps.
First, if you want to be extra-cautious, polyester will easily air dry in two to four hours. If you want to save a bit of electricity and avoid worrying about putting your garment in the dryer, you can hang it up in your shower, and it will be good to go in a couple of hours!
Second, consider using the cool dry (sometimes called tumble dry) setting on your dryer. Again, polyester dries quickly, and this way you can dodge the question of how much heat is safe for your garments.
However, most of us do one or two big loads of laundry a week, and it is certainly easier to throw everything into the dryer in a normal setting! This will not damage your polyester clothing, though to avoid static electricity build-up, you may want to stop the dryer cycle before it finishes and fish out the garments while they are just a tiny bit damp.
These tips also apply to various polyester blends, though we’ll consider those in detail in a moment.
How to Dry Polyester Fabric
Here is a quick guide on how to safely dry polyester fabric.
- Check the settings on your dryer and make sure you are not exposing your garments to temperatures above 100℉.
- If you have not already done this before the wash cycle, turn wet garments inside out before placing them in the dryer.
- Run almost all of the way through a normal heat or low heat dryer cycle, pausing a few minutes before it ends.
- Remove the slightly damp garments and hang them up to finish drying to avoid static electricity.
Do Polyester Blends Shrink in the Wash?
Poly blends are more likely to shrink in the wash than 100% polyester. Poly blends mix polyester fibers with other fibers, like cotton, rayon, or spandex. These blends create fabrics with unique and useful characteristics.
The additional blended fibers come with their unique qualities. For example, cotton shrinks massively in hot water. If you blend polyester with cotton, the polycotton will shrink more than 100% polyester.
This blend merges polyester and cotton fibers, usually in a ratio of either 50/50 or 65% cotton and 35% polyester. Polycotton dries quickly like polyester but breathes like cotton. This popular fabric often features in t-shirts and bedsheets.
Typically 100% cotton shrinks a lot during its first wash and then holds its shape more or less after that. Because of its high polyester content, polycotton resists wrinkling or shrinking under normal circumstances.
Unlike 100% polyester, polycotton cannot go through a warm water washing machine and hot dryer settings without shrinking. Hot water will shrink polycotton, so you need to be careful to wash these garments in cold water.
Any blend of polyester and cotton, whether 50/50, 65/35, or 60/40, will do best when washed in cool water to avoid the danger of the cotton shrinking in the wash. The polyester fibers protect the cotton fibers to a certain extent, though, because polycotton shrinks a lot less than 100% cotton!
Polyester and Rayon
This blend creates a light, silky material often used in dresses, underwear, and fancy blouses. The trick here is that rayon requires much more delicate care than polyester. To protect garments made out of this blend, you should either hand wash or use only a gentle, cold water cycle in the washing machine.
Do not place polyester-rayon clothing in the dryer. You should air dry these garments, either by hanging them up in the shower to drip-dry or by laying them flat on a towel to avoid any extra stretching.
Polyester and Spandex
Polyester and spandex make an excellent, stretchy blend that is perfect for yoga pants, bras, and athletic wear! You almost certainly own clothes made out of this fun, stretchy fabric. Do you find that these garments sometimes shrink or stretch into weird shapes in the wash?
To avoid damaging polyester-spandex clothes, put your clothes into a warm wash, followed by a cold rinse cycle. This blend can go into your dryer on a low heat setting.
You will need to either use a dryer sheet or remove the clothing before the dryer cycle ends to prevent static electricity build-up, which gets quite severe with this material!
Polyester and spandex blends range from as little as 5% spandex to a whopping 95% polyester and as much as 20% spandex and only 80% polyester. The higher the amount of spandex in the blend, the more delicately you should treat the garment.
For example, the label of your workout shirt might read “89% cotton 11% spandex.” This blend should survive a warm cycle in the washing machine and a low-heat spin in the dryer without any shrinking. For any garment that contains 20% spandex, you probably want to consider washing in a cold-water cycle and air drying.
How to Shrink Polyester
The flip side of the coin, as it were, is the situation where you actually need to shrink polyester clothing! You can shrink poly by applying controlled heat to make its fibers contract and shrink.
Maybe you ordered a shirt online, but when it arrived, you realized it was a bit too large for you. Can you shrink the shirt to make it fit?
Check the label inside your garment to find out if it’s 100% polyester or a poly blend (since you now know that blends will shrink much more easily!). One-hundred-percent polyester has to reach a temperature of at least 140℉ to shrink.
You can achieve this temperature through three simple methods.
The easiest, the most hands-off method uses your washer and dryer. “Wait,” you’re probably thinking. “Didn’t you just say the washer and dryer won’t shrink polyester?”
Well, yes–but now we’re going to talk about ramping up the heat settings on those everyday appliances.
Turn your garment inside out and run it through your washer on hot water settings. Then place it in the dryer on a high-heat setting. This extended exposure to high heat should shrink the garment.
You can also use an iron to force polyester to shrink. For this method, you’ll want to begin by soaking the garment and then rolling it up in a towel until it is just damp. Then turn the garment inside out, lay it flat on an ironing board, and cover it with a pressing cloth.
Set your iron on medium-low heat. Be careful here! Polyester will melt, scorch, or stiffen if it gets too hot under your iron.
Gently iron your garment through the ironing cloth until it is dry. Ironing is the most effective way to shrink your polyester clothing. It even works on 100% polyester, which can be very challenging to shrink.
Another way to shrink polyester is to dunk it in boiling water. Boil a large pot of water, remove it from the stove, and drop your garment into it. Let it soak for five to ten minutes, then remove the garment from the water, using tongs to avoid burning yourself.
Once it is cool enough to touch, roll it up in a towel to remove excess water, and then allow the garment to air dry.
How Much Can You Shrink Polyester?
One-hundred-percent polyester will not shrink very much. You have to take quite drastic steps to shrink it even a little because of its synthetic fibers. If you wear a medium size t-shirt, and you buy an XL thinking that you will shrink it down to size, you’re going to be disappointed.
There’s no handy equation along the lines of “if you iron wet polyester for five minutes, it will shrink two sizes.” This is a trial-and-error process. However, it is unlikely that you will be able to shrink polyester more than a size or two.
Another question to consider is how specifically you can shrink polyester. Here’s the thing: there is no easy way to make any fabric shrink exactly one size or shrink to fit the precise curve of your hips. You can shrink the fabric fibers, but be aware that the end result may not be as precise as you would like.
Can You Permanently Shrink Polyester?
While you can use high levels of heat to shrink polyester, nothing you do to fabric is truly permanent. As can see in this article, you can both shrink and unshrink polyester.
Unless you intentionally stretch out the garment, though, it will maintain its smaller shape after you shrink it. Wash the garment in cool water and allow it to air dry to help it maintain its shape. Conversely, if you would like to keep shrinking your garment, you can try continuing to wash it in hot water to see how far you can get it to shrink!
Does Polyester Shrink When Dry Cleaned?
Dry cleaning should not shrink or damage polyester in any way. The dry cleaning process is designed to protect delicate clothing and rarely causes shrinkage in any fabric.
Dry cleaning uses giant, computerized washer machines and a liquid solvent that contains very little water to wash clothes. These washers also employ giant coolers to prevent the garments from getting too hot during this process. The lack of water and heat means that most fabrics will not shrink during dry cleaning.
This makes sense because “dry clean” only garments are usually your delicates or sensitive fabrics like wool.
While dry cleaning will not harm polyester, you probably want to save your money because polyester does not require dry cleaning. It is tough enough to go in a regular wash cycle.
How to Unshrink Polyester
You can unshrink polyester by relaxing its fibers in a special soak and then using weights or pins to gently stretch it back into shape.
Unless you always go the extra mile of hanging up your clothes to air dry, you have probably experienced the dreaded realization that you accidentally shrunk a garment you really like. Don’t panic! Follow these steps to unshrink polyester.
- Fill a washtub or your sink with lukewarm water and a teaspoon or two of hair conditioner. Place your polyester garment in the water and let it soak for about fifteen minutes.
- While it soaks, prep a drying station: you’ll need a flat surface covered by a towel and either some rounded objects to use as weights or clothespins. (If you own a sweater drying rack, even better!)
- Remove the garment from the water. Gently rinse it under running water, but do not wring it out to dry it. Instead, press it between your hands just a bit to get out some of the water, and then roll it up in a towel until it is just damp.
- Take the garment to your drying station. Lay it flat, and then either hold down the edges with the weight or clip the edges to the towel with clothespins.
Once it is all the way dry, your garment should have regained its unshrunken proportions!
While you can certainly wash polyester in a regular washer and dryer cycle, you now know several tips for how to take the best possible care of your polyester clothing. You also know that either ironing wet poly or dipping it in boiling water will shrink the fabric, should you ever need to make your clothes a bit smaller!
Have you ever had difficulty taking care of polyester? Leave a comment below to let us know!