FAQ
Product Information
Why are Aiua's clothes made from 100% merino wool with no synthetic blends?
Most merino activewear brands mix in nylon, polyester, or spandex to cut costs or add stretch. The problem is that even a small percentage of synthetic material reintroduces the issues you're trying to avoid (microplastic shedding, odor buildup, and no biodegradability). We use 100% merino because the fiber already does what synthetics are engineered to imitate. It stretches, recovers, manages moisture, and regulates temperature on its own.
What does 150gsm mean, and why did you choose it?
GSM stands for grams per square meter — a measure of fabric weight. At 150gsm, our merino is lightweight enough for high-intensity training in warm conditions but substantial enough that it doesn't feel flimsy. It's a sweet spot that works year-round, whether you're running in July or layering under a jacket in December.
How fine is the merino wool you use
Our wool is 18.5 microns, which is about three times finer than a human hair. For context, traditional wool starts around 30 microns (hence the scratchy feeling). At 18.5, the fibers are fine enough to bend against your skin rather than poke into it, which is why our pieces feel soft rather than itchy.
What certifications does Aiua hold?
Three that we think matter. Our merino is RWS certified (Responsible Wool Standard), meaning it comes from farms that meet strict animal welfare and land management requirements. Our finished fabrics are OEKO-TEX Standard 100 certified, which means they've been independently tested and verified free of harmful chemicals and substances. And our manufacturing facilities are BSCI audited, ensuring fair labor practices and safe working conditions throughout our supply chain.
Where are your products made?
Our merino wool is sourced from RWS-certified farms in Australia, and our garments are manufactured in facilities that meet BSCI audit standards in Vietnam. We chose partners who could meet our material and ethical standards without requiring us to compromise on either.
Do you use Superwash?
To make our merino machine-washable and resistant to shrinkage, we use the chlorine-Hercosett process, commonly known as Superwash. We've evaluated alternatives like plasma treatment, but they tend to degrade the fiber, are less effective at preventing shrinkage, or are prohibitively expensive — and usually all three.
Superwash gets scrutiny in sustainability circles, and we think that's fair. But the environmental case is stronger than its reputation suggests. A 2024 study found that Superwash-treated wool does not shed microplastics and remains fully biodegradable, actually breaking down more quickly than untreated wool. So while the process isn't perfect, we believe the tradeoff is worth it: making merino practical enough for everyday use means more people can move away from synthetic activewear entirely.
We're actively watching developments in this space and hope to adopt a stronger alternative as the technology matures.
About Merino Wool
What makes merino wool different from regular wool?
Merino wool comes from merino sheep, which produce fibers far finer than traditional wool (around 18–24 microns compared to 30+ for regular wool). At that fineness, the fibers bend against your skin rather than poking into it, which is why merino feels soft where traditional wool feels scratchy. It's also naturally moisture-wicking, temperature-regulating, and odor-resistant. Synthetic fabrics try to replicate these properties through chemical treatments, but that merino does it all on its own.
Is merino wool itchy?
No. The scratchiness people associate with wool comes from coarse fibers (30+ microns) that are stiff enough to poke into the skin. Our merino is 18.5 microns (about three times finer than a human hair) so the fibers flex on contact rather than irritate. Most customers tell us it feels softer than cotton.
Is merino wool itchy like regular wool?
Not at all. Our premium merino wool has ultra-fine fibers that feel soft and smooth against your skin. Many customers say it feels even softer than cotton or synthetic materials.
Why does merino wool resist odors?
Merino wool is naturally antimicrobial. The fiber's structure prevents odor-causing bacteria from accumulating the way they do in synthetic materials, where they embed in the plastic and persist through wash after wash. You can wear merino multiple times between washes without any smell building up. We go deeper into the science here.
Why does merino activewear cost more than synthetic?
https://aiuaclothing.com/blogs/news/is-merino-wool-worth-the-price-a-5-year-cost-analysis?_pos=2&_sid=1476c23fc&_ss=rSynthetic activewear is made from petroleum-based plastic. It's cheap to produce, and the price reflects that. Merino wool is a natural fiber that's sheared once a year, processed carefully to preserve its properties, and certified at multiple stages: RWS for animal welfare, OEKO-TEX for chemical safety, BSCI for fair labor. That supply chain costs more than extruding polyester in a factory.
But cost per wear tells a different story. Merino lasts longer with proper care, doesn't need to be washed after every use, and won't develop the permanent odor that forces you to replace synthetic gear every few months. Over the life of the garment, merino is often the better value. See our analysis here.
How is merino wool more sustainable than synthetic activewear?
Synthetic activewear is made from plastic, and every wash sends microplastic fibers into waterways. Those fibers don't break down; they accumulate in oceans, soil, and eventually in us. Merino wool is a renewable, biodegradable fiber. It breaks down naturally at end of life, sheds no microplastics, and because you wash it less often, it uses less water and energy over its lifespan. Learn more on our Why Wool? page.
Product Care
How do I wash my merino wool activewear?
Machine wash on a gentle cycle in cool water (30°C / 86°F or below) with a wool-specific or mild detergent. Avoid fabric softener and bleach. Softener coats the fibers and reduces their natural moisture-wicking ability, and bleach will damage the wool. Turn pieces inside out before washing to minimize surface friction.
How often should I wash my merino wool activewear?
Less frequently than you'd think. Merino's natural odor resistance means you can wear pieces 2–3 times between washes for most activities, or after each intense workout where you've really sweated through it. Washing less frequently extends the life of the garment and reduces water usage compared to the wash-after-every-wear cycle that synthetic activewear demands.
Can I put merino wool in the dryer?
We recommend laying flat to air dry, away from direct heat or sunlight. Merino dries faster than you'd expect. If you need to use a dryer, use the lowest heat setting for a short cycle, but air drying is the safest way to preserve the fabric's shape and performance over time.
Will my merino wool pieces shrink?
Our merino is treated specifically to prevent shrinkage in the wash. Follow the care instructions — cool water, gentle cycle, air dry — and your pieces will hold their size. Hot water and high heat are the main risks, which is why we recommend keeping the dryer out of the equation when possible.
Fit & Sizing
How does merino wool fit compared to synthetic activewear?
Our pieces are designed with an athletic fit, close enough to move with your body without being compressive or restrictive. Merino has natural stretch and recovery, so it gives where you need it and returns to shape afterward. If you prefer a more relaxed fit, we recommend sizing up. Check our size chart for specific measurements.
What if the size doesn't fit perfectly?
We offer free exchanges within 30 days
of purchase. Visit this page to get the ball rolling and we'll send you a different size.
Does merino wool stretch out over time?
Quality merino maintains its shape well. The fiber has natural elasticity, allowing it to stretch during movement and recover when you're done. You won't get the bagged-out knees or sagging hems that happen with cotton over time.
Performance
Can I wear merino wool for intense workouts?
Yes. Merino excels in high-output situations. The fibers wick moisture efficiently and regulate temperature in both directions, keeping you cool during a hard session and comfortable when you cool down afterward. It performs across everything from hot yoga to HIIT to long-distance running.
Will merino wool make me too hot?
No. Merino is thermoregulating, not insulating. It responds to your body and your environment, cooling you when you're warm and warming you when you're cold. That's a fundamental difference from synthetics, which trap heat, and from heavier wools, which are designed primarily for warmth. At 150gsm, our pieces are built for movement and breathability, not bundling up.
How does merino compare to synthetic materials for athletic performance?
Merino matches or outperforms synthetics in every category that matters during a workout. It wicks moisture just as effectively, but because wool fibers absorb up to 30% of their weight in water vapor before feeling wet, you skip the clammy, stuck-to-your-skin feeling that polyester is known for. It regulates temperature in both directions: cooling you during a hard session and insulating when you step outside afterward. And unlike synthetics, merino is naturally antimicrobial, so odor doesn't build up in the fabric over time. Your tenth wear smells like your first.
The bigger difference is what happens off your body. Synthetic activewear is made from plastic, and it sheds microplastics into waterways every time you wash it. Merino is a natural fiber: biodegradable, renewable, and free of petroleum-based fabrics. Performance shouldn't come at the cost of the environment.
Is merino wool good for sensitive skin?
Yes. Merino is naturally hypoallergenic and far gentler than synthetic fabrics, which can trap heat and irritate skin through friction and chemical treatments. The fine fibers (18.5 microns in our case) sit smoothly against the skin without causing the prickling or chafing that coarser materials can.
Can I work out and then wear it the rest of the day?
Yes. As a matter of fact, it's why we chose to work with merino wool. Because it manages moisture without trapping odor, you can train in the morning and wear the same piece through the rest of your day without needing to change. It dries quickly, doesn't hold odor, and looks clean enough that nobody will know you just came from the gym. It's one of the reasons we think merino is the most practical performance fabric: it doesn't force you to plan your day around your workout clothes.
Orders & Shipping
What's your return policy?
We offer a 30-day satisfaction
guarantee. If you're not completely happy with your purchase, return it for a
full refund or exchange, minus shipping costs. Items should be in original
condition. You can initiate a return online here.
How long does shipping take?
We ship within 1-2 business days.
Standard shipping takes 3-8 business days. Orders over $100 ship free.
Do you ship internationally?
At the moment we only ship within the United States.