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Does Merino Wool Shrink After Washing?

Does Merino Wool Shrink After Washing?

Merino wool is often considered one of the most comfortable fabrics. It’s warm, soft, moisture-wicking, breathes well, and has antimicrobial properties. However, some people are concerned about whether or not merino wool will shrink after being washed. Is this true? Does Merino wool shrink after washing?

Yes merino wool will shrink after wishing, but not if you follow the proper instructions. Wash with cool or cold water and allow your clothing to air dry. Never apply heat during the wash or dry cycle.

Washing Merino Wool: Will Merino Wool Shrink In The Wash?

Yes Merino wool will shrink if you don’t follow proper washing and drying directions. I’ve accidentally shrunken wool a few too many times, and you end up with a garment that’s half its original size. My mens XL sweaters wouldn’t fit on my 10yo nephew after accidentally washing them with hot water.

When I first started buying merino wool clothing, I would dread washing it. All it took was one unfortunate experience with an expensive sweater for me to fear washing my wool. I was so worried about shrinking my wool garments that I’d hand wash and hang dry everything to prevent shrinkage. I’d toss my wool sweaters and base layers in a hamper and that’s where they’d sit for months at a time.

After a bit of research I realized that there was a much easier way to wash wool. You can wash merino wool in the washing machine, but it will shrink if you don’t follow the proper wash directions.

Why Does Merino Wool Shrink?

Why does merino wool shrink?

Wool is surprisingly durable compared to other similar weight fabrics, but shrinking is a serious concern. There are 3 main culprits behind shrinking merino wool- Moisture, Heat, and Agitation.

  • Moisture: Moisture causes the fibers to expand as they soak in water. That expansion fills in the gaps in the weave and tightens up the thread. Allowing wool to air dry naturally will allow the fiber to relax, but you will likely experience minimal shrinking after the first soak (unless heats applied).
  • Heat: Heat will cause wool fibers to contract. This is the source behind 99% of cases of shrinking wool. Never use heat in any steps in the wash or dry process. It’s a guaranteed way to ruin merino wool clothing.
  • Agitation: Agitation is another problem that can cause excessive shrinking. As the wool is spun and agitated the fibers are stretched out beyond their original length and the hair shingles won’t orient in the same direction. This isn’t a huge issue with cool/cold washes, but heat causes those fibers to flare out and snag onto each other, intertwine, and compact the wool.

How To Wash Merino Wool Without Shrinking It

How to wash merino wool without shrinking

Wool garments can be hand washed, machine washed, or dry cleaned (damages fibers over time). Just make sure you use cold water and a gentle wool-safe laundry detergent (my favorite). Hand washing wool is self explanatory, pour in some detergent, and work through the wool in cold or luke warm water (Never Hot).

You need to follow extra precautions when washing merino wool in a washing machine. Set the temperature setting to either cold or cool and use the gentle wash setting. I like to wash my Wool in an Extra Large Mesh Laundry Bag (made for delicates). This is especially important if your machine has an agitator, but it will help prevent holes/tears in any machine.

If this is your first time washing merino wool, here’s a few things you need to keep in mind when washing wool.

  • Start With Fresh Water: If you’re hand washing merino wool, you need to start every garment with fresh water. Drain the sink/bucket between each article of clothing so that you get rid of previous dyes or anything that could stain/damage your wool. Even if you can’t see anything, it’s better to get rid of the water between washes. In a washing machine, you should run an empty rinse cycle to remove bleach/chemicals, and separate garments by light/dark colors.
  • Use Cool or Cold Water: Never wash or dry wool clothing using any kind of heat. Don’t use hot or warm water when you wash/rinse, don’t use a dryer, and never leave your garment near a radiator or vent to speed up drying.
  • Wash Merino Wool Gently: Hand washing is the safest way to wash wool, but you can usually get away with washing it in the washing machine on a gentle/delicate cycle. I always use a Mesh Laundry Washing Bag whenever I’m washing wool garments. It might not be necessary, but it helps prevent holes and stretching wool.
  • Rinse Thoroughly: It’s really hard to get all of the soap out of wool when you’re hand washing, but you don’t want to leave behind remnants of soap. I’ve had bubbles pop up on my sweater once I started to sweat.
  • Dry Carefully: Avoiding heat is the most important step for drying wool. That means keeping wool out of the dryer and away from external heat sources. There’s a bit of a debate on whether you should hang dry or flat dry merino wool. I’ve heard that flat drying wool causes shrinkage (probably minimal), but the weight of hang drying can cause it to stretch. I have lots of wool, so I always hang dry it, and I’ve never had any noticeable issues.

Is It Better To Dry Clean Merino Wool?

Is It Better To Dry clean merino wool?

You don’t always need to follow the directions on the care tag on your clothes. Yes, you can ignore the tags that say dry clean only and save some money by washing your wool garments at home.

Most people are under the false impression that it’s better to dry clean merino wool. That may be the case if you’re using harsh chemicals and don’t know how to avoid shrinkage, but dry cleaning is actually worse for your clothes.

Dry cleaning uses harsh caustic chemicals that can shorten the lifespan of delicate natural fibers. They’ll lose their luster and contribute to unnecessary wear and tear on the material.

Think about this for a second. Merino wool is made out of animal hair and how often do you think sheep get dry cleaned on the farm? They get cleaned by the rain and the sun dries them off naturally.

Although merino wool, cashmere, etc. may say “Dry Clean Only”, wool rarely needs to be dry cleaned. Most modern wool garments can be washed in a domestic washing machine and it’s always safer to hand wash.

How Much does Merino Wool Shrink?

Merino wool usually won’t shrink if you follow the proper wash and dry instructions. Unfortunately, life gets in the way and sometimes you forget to separate your merino wool laundry. How much does merino wool shrink?

How much a wool garment will shrink depends on the blend, weave, and how its treated. Sometimes wool will shrink like crazy and other times it may go down a size or two.

I’ve learned this the hard way and completely destroyed an entire load of sweaters. Every garment was slightly different, but they all shrunk some. Most of them shrunk down a size, but a few of my favorite sweaters went from an XL to a Medium (possibly smaller).

I was basically left with a bunch of long sleeved belly shirts. There was at least 6 inches of space between my beltline and the bottom hem of the sweaters. With light/moderate shrinkage, you should be able to unshrink the wool (I explain below).

Modern Wool Is Less Likely To Shrink

Wool on a live sheep hasn’t been processed. It’s highly elastic, stretched out, and the fibers all point out away from the sheep’s body. This uniformity helps prevent tangling and guards against the interlocking that happens after laundering.

Once the sheep’s hair gets woven into merino wool clothing, it’s weaved together and given a mixed/unnatural orientation. Manufacturers understand that those fibers will bind up and contract, so they takes steps to minimize shrinking.

They treat the wool clothing in a specialized wash to control the fibers and minimize shrinking even in the presence of heat, moisture, and agitation. It’s still a good ide to wash your wool on a cold/cool delicate cycle, but there’s less of a risk of shrinking modern merino wool.

Can I Unshrink Merino Wool?

You can usually salvage shrunken merino wool, but it’s not easy. Remember that the three main culprits behind shrinking/stretched wool are moisture, heat, and agitation. We can use some of these elements to reverse the shrinking process!

  1. Fill A Tube With Lukewarm Water (Not Hot)
  2. Dissolve a generous amount of wool conditioner into the water. You can find wool-specific conditioners, but I’ve always used the conditioner my wife uses in her hair. Tossing a little bit of wool detergent (my favorite) into the water will help emulsify the conditioner into the water.
  3. Allow the wool garment to soak for 20-30 minutes (or longer). You can help speed this along by squeezing water through the garment to evenly saturate the wool.
  4. Squeeze out the extra water and lay the merino wool garment flat on a towel. You can use a sheet or blanket if you’re working with bigger items. Lay a second towel over top of the item and squeeze out most of the remaining water. Once your done squeezing it should feel slightly damp (not soaked or completely dry).
  5. Reshape the item and try to loosen up the contracted fibers. Work from one section of the garment to the next and try not to overly stretch or misshape the wool. This needs to be done before the garment dries completely. Don’t’ use clips or weights to hold any parts of the garment in place, because it will crease the fabric.
  6. You may need to repeat this process on heavily shrunken wool.
  7. Once your satisfied with the reshaping, rewash your merino wool and allow it to air dry. You will need to get all of the conditioner and detergent out so you don’t end up with a sudsy mess the next time you wear it.