How to Unshrink a Sweater With Hair Conditioner

by Danielle

I shrank my favorite sweater. Not a little. The sleeves-end-at-my-elbows kind of shrunk.

It was a thick oatmeal wool crewneck I'd worn every weekend for three winters, and it went into the dryer with a load of towels by accident. It came out stiff, scratchy, and about two sizes too small. I folded it up, put it on the donate pile, and felt a little sad every time I walked past it.

Then my sister mentioned she'd saved a cashmere cardigan by soaking it in hair conditioner. That sounded way too easy, but the sweater was headed out the door anyway, so I had nothing to lose.

It worked better than I expected. The whole thing takes about 45 minutes of actual effort, plus a day or two of drying flat, and all you need is stuff that's already in your bathroom.

Tools and Materials:

• One shrunken or stiff sweater (wool, cashmere, merino, or alpaca work best)
• Hair conditioner, about 2 tablespoons (any inexpensive kind works)
• A clean sink, tub, or large bowl
• Two large bath towels
• A measuring tape (optional, but helpful)
• Rust-proof pins or a few heavy books (optional, for holding the shape while it dries)

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1. Measure it first
2. Mix the conditioner
3. Dunk and soak
4. Squeeze, don't wring
5. Stretch it back into shape
6. Dry it flat
Extra tips for better results

Measure armpit to armpit and shoulder to hem, so you have a target when it's time to reshape.

1. Measure it first

Before it gets wet, lay the sweater flat and measure across the chest and down the length. Then grab a sweater that fits you the way this one used to and measure that too. Now you know exactly how much stretch you're aiming for.

Mix until the water is evenly cloudy. Undissolved blobs can leave slick spots on the knit.

2. Mix the conditioner bath

Fill your sink with lukewarm water. Aim for bathwater warm, not hot, since heat is what shrank it in the first place.

Squeeze in about 2 tablespoons of conditioner and swish it with your hand until the water looks cloudy and there are no blobs left.

Press the sweater under until no dry patches float on top.

3. Dunk and soak

Push the sweater under the water and press gently until it's fully saturated. Then leave it alone for about 30 minutes. If it's badly shrunk or really stiff, you can go up to an hour, but don't leave it overnight. A long soak can weaken the fibers.

The conditioner coats and relaxes the fibers, which is what lets the knit loosen up enough to stretch back out.

Rolling it in a towel pulls out most of the water without any twisting.

4. Squeeze, don't wring

Skip the rinse. You want the conditioner to stay in the fibers while you reshape. Lift the sweater out in a bundle (it's heavy when wet and can stretch in weird places if it dangles) and press the water out between your palms.

Then lay it flat on a bath towel, roll the towel up like a burrito, and press down along the roll. The sweater should come out damp, not dripping.

• Don't twist or wring it, which can distort the knit

• Keep it damp for the next step, since dry fibers won't stretch

Weighing down the cuffs and hem holds the new shape while the fibers set.

5. Stretch it back into shape

Lay the sweater on a second dry towel. Now work slowly, a little at a time. Gently pull the body wider, then longer. Tug the sleeves out toward where the cuffs should land. Check against your measurements as you go.

If you hit resistance, stop pulling in that spot and move to another area. Short, gentle tugs all over work better than yanking one section.

6. Dry it flat and pinned

Once it's close to your target size, keep it there while it dries. Pin the edges to the towel with rust-proof pins, or set a few heavy books along the hem and cuffs. Leave it somewhere out of direct sun until it's completely dry, usually a day or two.

When it's about halfway dry, give it one more gentle stretch. That's when it usually gives you a little extra length.

Extra tips for better results

Check the fiber first. This works on animal fibers like wool, cashmere, merino, and alpaca. Acrylic and polyester don't respond the same way, so a synthetic sweater probably won't budge much.
Be realistic about badly felted sweaters. If the knit has matted into something that looks more like felt than yarn, you'll likely get some softness back but not the full size. Expect it to come back closer to its original size, not necessarily all the way.
Try it on scratchy sweaters too. Even if nothing shrank, a quick conditioner soak can take the itch out of a stiff wool sweater. Just skip the heavy stretching and dry it flat in its normal shape.
Repeat if you need to. If it's still a little snug once dry, you can do a second soak and stretch.