Over the last few weeks we've seen a huge increase in the number of questions to our team about the difference between Down and Synthetic Insulation.

With more cold weather likely over the coming months, we thought we could use this week's newsletter to provide a brief guide for those of you making a decision between the two.

So - what are the options?



Down is a type of feather found underneath the tougher exterior feathers of birds.

It is a fantastic thermal insulator, and is very lightweight, meaning that it is great for lightweight, high performance insulation.

However, if down gets wet it loses almost all insulating properties and forms clumps. If left to dry this will cause clothing to be lumpy, and in some cases smelly.

Many brands have developed a way to treat down to give it a water repellent coating, but it is not completely waterproof.

Almost all down used within the Outdoor Industry is RDS-accredited, which means it is a byproduct of the meat industry.

Down is not currently widely recycled, but our friends at Mountain Equipment are leading the charge on recycling down with their Down Cycle initiative.



Synthetic Insulation is usually produced using recycled or raw polyester. This is engineered into a structure similar to down in order to provide insulating properties.

Synthetic down isn’t as good at insulating as down, which means you need more of it for the same warmth. Importantly though, it retains insulating properties when wet and doesn’t clump up like down.

Synthetic Insulation is also normally a lot cheaper than down.

Synthetic Insulation can be made of fully recycled and recyclable polyester, but even recycled, Synthetic Insulation has a greater carbon footprint than most down.

Synthetic Insulation has the benefit of containing no animal-derived materials, which completely eliminates the risk of inadvertently using down sourced from less humane sources.

So, what should you choose?

In summary, this really depends on what you will be doing, but at the risk of a bit of controversy we've produced a simple guide below;

Use Down if;

  • You need high-performance, lightweight insulation
  • You will be keeping the clothing dry (or you are prepared to take the time to care for it by reproofing & cleaning)
  • You are prepared to spend more for the higher performance

Use Synthetic if;

  • You will often be getting your clothing wet (and you're not good at reproofing!)
  • Weight / Packability isn't a primary consideration
  • You want to avoid wearing clothing containing animal product