What happens to a merino jacket in the rain? Myths busted
Autumn here is more often wet than sunny — and we get asked regularly: "Does a merino jacket get soaked?" and "What if it gets wet — does it still keep you warm?" Today we clear it up.
1. The natural structure of wool
Wool fibres have a slightly hydrophobic (water-repelling) outer layer and a core that can absorb moisture — which is why light raindrops often sit on the surface or are repelled altogether. Thanks to this structure, wool can absorb up to around 30% of its own weight in water before you feel damp against your skin.
In practice: the jacket doesn't soak through instantly — the outer fibres hold their ground while the interior of the wool responds to moisture gradually.
2. Does merino still warm when wet?
Yes — and that's one of the reasons wool is chosen for outerwear. When it gets damp, the adsorption process (moisture absorption at fibre level) releases a small amount of heat, which means the jacket can still insulate.
It doesn't work like an umbrella — but for a while it helps maintain thermal comfort, especially if the layer underneath stays dry.
3. The limits — what a merino jacket won't do
- It's not waterproof — heavy rain or a prolonged downpour can penetrate to the inner layers.
- It doesn't replace synthetic membranes — if you need full protection in extreme conditions, pairing merino with an outer rain shell is a good idea.
- When wool becomes fully saturated, insulation efficiency drops — more moisture means more heat absorbed by the water.
4. What to do when your merino jacket gets wet
- Shake it out — a gentle shake removes excess water.
- Dry naturally — lay flat in a well-ventilated spot, away from radiators and direct sunlight.
- Avoid the tumble dryer — high heat can damage the fibre structure.
- Air out and freshen with frost — if the jacket is slightly damp, these methods help restore its properties.
A merino wool jacket isn't a waterproof umbrella — but thanks to its natural properties it handles moisture better than most materials. On wet days we can't promise it'll stay perfectly dry, but warmth and comfort tend to last longer than you'd expect.
