Merino Short - 5"
Designed for everyday movement in merino.
Shop nowHow to Wash Merino Wool Properly (Without Shrinking It)
Washing merino wool is one of the most misunderstood topics online. Thousands of Reddit threads ask the same questions:
“Why did my merino shrink?” “Do I need special detergent?” “Can you put merino in the dryer?”
This guide explains the real science of wool fibres, how shrinking happens, and how Estroni’s 95/5 blend improves wash performance.
1. The Correct Way to Wash Merino Wool
Merino wool is naturally antibacterial — it doesn’t need aggressive washing. Follow these simple guidelines:
Best washing method:
- Cold wash only
- Gentle or wool cycle
- Wool-safe detergent (pH-neutral)
- Wash inside-out
- Never tumble dry
Most shrinking and damage comes from mechanical agitation + heat, not the water itself.
2. Why Merino Wool Shrinks
Wool fibres have microscopic scales on their surface. When exposed to:
- hot water
- high heat in dryers
- heavy agitation in washing machines
…these scales interlock permanently — a process called felting.
Once merino shrinks from felting, it cannot be reversed.
3. Is Machine Washing Safe?
Yes — with the right settings.
Cold water + gentle cycle is perfectly safe for merino wool, especially blends.
What you must avoid:
- Warm / hot water cycles
- “Heavy duty” or “cotton” cycles
- Fabric softeners (coat fibres, reduce performance)
- Detergents with enzymes (can weaken protein-based fibres)
Read next: Why 100% merino develops holes →
4. Why You Should Never Tumble Dry Merino
The dryer is the #1 cause of merino shrinking.
The heat + tumbling causes:
- Felting (permanent shrinkage)
- Fibre fatigue
- Loss of softness
- Distortion of garment shape
Always air dry flat.
5. What Detergent Should You Use?
- Choose wool-safe detergents (pH-neutral)
- Choose detergents that say “for delicates” or “for wool”
- Avoid anything with enzymes or bleach
Good detergent categories:
- Wool wash liquids
- Delicate detergents
- Laundry solutions designed for protein fibres (silk/wool)
6. Why Merino Stays Fresh Longer (You Can Wash Less Often)
Merino wool naturally resists odor due to:
- Keratin-based fibres that inhibit bacteria
- Moisture absorption into the core of the fibre
- Low surface moisture → bacteria struggle to multiply
Most merino can be worn multiple times between washes — which dramatically extends garment life.
Read: Why merino resists odor →
7. Does Elastane (5%) Change Washing Performance?
No — and it actually improves it.
Estroni’s 95/5 blend was chosen because elastane:
- Improves stretch & recovery
- Reduces fibre stress during washing
- Lowers the risk of shrinkage (as long as no heat is used)
Odor resistance is unchanged because that comes from wool’s chemistry — not the elastic fibres.
See the full 100% vs 95/5 comparison →
8. Quick Summary: How to Avoid Shrinking
- Cold water only
- Gentle/wool cycle
- Wool-safe detergents
- No heat, ever (washing or drying)
- Air dry flat
