How to unshrink merino wool

19 August 2024

merino wool is known for its resilience, softness and versatility, and at icebreaker most of our clothing is machine washable for easy care. However, we understand the distress it may cause if you forget to read the care label, or if an item accidentally sneaks into the dryer, leaving your favourite merino item looking worse for wear.

Even though merino's fine fibres can become damaged if not properly cared for, the good news is that it's sometimes possible to reverse the dreaded merino wool shrink by following this handy guide - to help safely restore shrunken items to their original size.

 

Understanding merino wool

Merino wool comes from the special breed of merino sheep, native to New Zealand. Famously warm, soft against your skin and breathable, merino's moisture management properties, temperature regulation and natural odour resistance make it a popular choice for base layers mid layers and outer layers in all weathers. 

Although its resilience and softness also makes it great for high-performance kids clothing and activewear, merino wool fabric can require special care in order to maintain the unique properties of the delicate natural fibres. Washing at high temperatures, using tumble dryers and adding harsh chemicals to the machine can lead to merino wool shrinkage.

 

Why does merino wool shrink?

Although most merino wool items are naturally stretchy and can be safely hand-washed or washed in the machine in cool water, not following the care label correctly could lead to your merino shrinking after washing or drying. 

Washing or drying at high temperatures can cause the lightweight wool fibres to expand and contract, making merino wool shrink when it dries. Over-agitation of the fibres, on using an intense cycle in the machine, can also lead to shrinkage as the fibres can lock together causing damaged and misshaped separates. But can you unshrink merino wool? In some cases it might be possible to reverse the problem, but it cannot be guaranteed, so to avoid shrinkage it's best to always:

• •Wash on a cool, gentle cycle - high temperatures can lead to shrinkage, so always wash in cooler water and take care not to agitate fabrics.

• •Avoid bleach or fabric softener - harsh chemicals can affect the natural wool fibres, so choose wool-friendly options. Rinse thoroughly to keep wool looking its best.

• •Air dry - although our socks can usually be popped in the dryer on a low heat, other merino wool items should be gently hung to air dry.

• •Check the care label- every item's care label has unique instructions, giving helpful information for the best way to wash and dry your clothing.

How to unshrink merino wool: Step-by-step guide

So, how can you unshrink merino wool after washing, to restore the item to its original shape? Fortunately, there are some tried-and-tested ways to learn how to unshrink merino wool mens hoodies, womens sweaters and tops, should the worst happen in the wash. These are some suggestions, but be sure to read the product's care label, and any specific instructions for each item, before you begin.

Step 1. Fill a basin with lukewarm water

Gently soak the item in a bowl or sink filled with lukewarm water. Be sure to not use hot water to avoid any further shrinking.

Step 2. Dissolve a wool-specific conditioner in the water.

Add a generous amount of wool conditioner to the water - it's recommended to use a special wool-safe conditioner, or it may be possible to use a very gentle hair conditioner. Always perform a patch test first to ensure colour-fastness.

Step 3. Leave to soak

Leave the clothing to soak for a maximum of half an hour. Do not scrub or agitate the fibres.

Step 4. Remove from the water and lie flat

Remove the item and very gently squeeze out the excess water before laying it flat on a clean, dry towel.

Step 5. Gently re-shape

Re-shape the item to its original form whilst it's still damp. It's important not to use pegs or weights to pull the garment into shape as this can cause further damage.

Step 6. Wash and dry the item as usual

Once dry, very gently wash the item again in cool water and air dry as per the care label. Your clothing should now be back to its original shape.

This process can be repeated if the item has shrunk severely, or isn't back to its original form after the first attempt. It's worth noting that results cannot be guaranteed using this method; the only sure-fire way to counter shrinkage is by avoiding it.

Tips for preventing future shrinkage

caring for merino wool correctly will mean your favourite items will perform at their best for as long as possible. Washing and drying your merino clothing in the right way will help to preserve its softness, temperature regulation and moisture managing properties, as well as avoid shrinking. Here are our top tips:

• •Always follow the care label for every garment. Although some may be able to be washed and dried with other items, others may be more delicate.

• •Use a cold cycle in the machine, or hand wash, at no more than 30 degrees C.

• •Rough washing cycles and putting merino wool in with items that may catch - such as zips and velcro - is more likely to damage it, so keep these separate.

• •Ensure washing machine cycles are no faster than 500 revs per minute to help preserve the shape of the natural fibres.

• •Avoid using strong detergents or bleach. Opt for wool-safe detergent and skip the fabric softener.

• •Wash dark and light colours separately.

• •Air dry your clothes rather than tumble dry.

• •Store your garments gently folded, away from moisture and direct sunlight.

How to unshrink merino wool - Summary

Can you unshrink merino wool without causing further damage? Although it's best to avoid the risk of shrinkage in the first place by taking care of your high-performance fabrics, soaking any mis-shaped items gently in wool conditioner and re-shaping whilst damp offers a solution for how to unshrink merino wool sweaters and t-shirts at home. 

Caring for your merino garments in the right way - by avoiding heat or fibre damage - will help keep them looking their best, stay naturally odour resistant, breathable and help them to last longer. Shop merino wool range and discover your perfect layering solution for all seasons.

How to unshrink merino wool - FAQ

Can you reverse shrunken wool?

It's usually possible to reverse shrunken wool items by soaking them in lukewarm water, applying special wool conditioner and re-shaping them whilst damp. Avoiding extreme heat helps protect delicate wool fibres from expanding and contracting, which can cause damage and shrinkage.

Will 100% merino wool shrink?

Even 100% merino wool items can shrink if not properly cared for. Merino is a natural product which can be damaged during hot washes, when exposed to certain chemicals, or when put in the tumble dryer. Be sure to always follow the care label to keep your items in shape.

Can shrunken wool be restored?

Wool can shrink when its fibres become damaged by heat or agitation. It can be possible to use the 'soak, condition, re-shape' method to restore your items, before washing them again on a gentle cycle as per the care label. Very shrunken items may need several treatments.

How to unshrink a merino wool hat?

If you accidentally put your merino wool hat in a hot wash, or in the tumble dryer, it may be possible to reverse the damage by soaking it in tepid water, adding some wool conditioner to the water and gently wringing and re-shaping it before it fully air dries. 

Can you fix a merino wool sweater that shrunk in the wash?

Wondering how to unshrink merino wool sweater? If your favourite merino sweater got into a hot wash by accident, you'll need to soak the sweater first in lukewarm water, add wool conditioner to the mix, and leave to soak. Reshape flat whilst damp before washing again on a cool cycle.