Thermore Ecodown – your synthetic alternative to down

Want to head outdoors but not loving the weather forecast? While down remains a favourite for those seeking warmth in their jackets, it isn’t your only choice when it comes to insulation. Ecodown is a synthetic option that can keep you warm, even in damp conditions – and Thermore™ is a leading player in this field.


Founded in Milan in 1972, the team at Thermore are global experts in sustainable insulation technology, being the first to recycle polyethylene terephthalate (PET) bottles into thermal insulation.

Ecodown™ technology (along with their sustainable footprint) makes Thermore ideal partners for us at Kathmandu.

What is Ecodown synthetic insulation?

It’s the best of both worlds – embracing the versatile, sustainable threads of synthetic insulation, with the warmth and loft that down offers.

Ecodown synthetic insulation is created from 100% recycled polyester. Post-consumer PET bottles are broken down into resin and reinvented as polyester fibers. These ultrafine fibers become the fill in your Thermore jacket, trapping warmth within air pockets and mimicking the insulating effects of down.

Thermore Ecodown is able to imitate the qualities of down, even when your jacket gets damp. The end result is a high performing, super-durable insulating jacket with extra resistance to water.

You can read more about our recylced polyester initiatives here. 

Woman walking in the Cuban rainforest
If expecting some light rain, the Heli Thermore Jacket will continue to keep you warm

Why choose a Thermore Ecodown jacket?

Ecodown has many years’ research and development behind it – meeting its aim of creating a quality alternative to down insulation.

Compared to traditional down, a jacket with synthetic Thermore Ecodown loft fibers has some significant advantages, such as:

  • Keeping you insulated even in slightly damp conditions
  • Not clumping or getting cold spots after being washed
  • Fast drying times

Ecodown is crafted in a unique multi-shaped structure that’s designed to provide superior loft, warmth and recovery when compared to down insulation.

If you have an allergy to duck or goose plumage, choosing a synthetic alternative like Ecodown is a great insulation solution.

A man hiking in Cuba in Thermore jacket
Your Heli Thermore is ideal for cool mornings or evenings

Introducing our Heli Thermore Jacket

The opportunity to harness Thermore’s Ecodown loft fibers was one we couldn’t ignore. This incredible synthetic material is now insulating a couple of our Heli jackets, with significant benefits like:

  • The equivalent warmth of 600 fill power down
  • PETA approval as a vegan product
  • 100% recycled fiber fill
  • Drying quicker than a standard down jacket
  • bluesign® approval to ensure environmental friendliness

Take a closer look at our Heli Thermore Jackets


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