Getting the Lowdown on Down

Down is one of the most important clothing/gear insulators used today. Even with the advances in synthetic insulators, nothing can beat the weight to warmth ratio of good quality down. Today, I’m going to talk about what to look for when buying down stuff.

First off, what is down? Down is the fine layer of feathers beneath the outer layer of large feathers of adult ducks, geese and other water foul. It has incredible loft and therefore is able to trap air and create an insulating layer for its wearer. It is not cost effective to raise birds just for their down, so down collection is a secondary activity to whatever the birds are raised for. Low quality down is usually gathered from young geese (4 months) raised for consumption whereas high quality down is collected by hand from molting adult birds used for breeding. Therefore, due to turnaround time and effort, the high quality down is very rare and expensive. However, it is this high quality down that makes the best jackets, sleeping bags, pants, boots, etc. I alluded to this a big in my sleeping bag shootout, where clearly the high quality down bag performed best.

So now you might be asking yourself, “how can I determine what quality of down I’m buying?” It’s actually pretty simple. All down products are rating with something called “Fill Power”. Fill power is the amount of “loft” a given weight of down has. The more loft you have, the more air that is trapped in your clothing, which means that its warmer. Fill power is rated in cubic inches per ounce. A high number means that you will have excellent insulating properties while carrying minimal weight. A low number means that you will either be less warm with a given weight of down or you’ll have to carry more weight to be just as warm as a higher rated down.

Here’s an easy scale of the typical fill power ratings:

400-450: Medium quality

500-550: Good

550-750: Very Good

750+: Excellent

** Most if not all high altitude gear is made with 750 or higher down. You don’t want to be lugging extra weight all the way to 8000m!

Here are some examples of down jackets.

From left to right:

1. Mountain Hardware Absolute Zero – 800 Fill:

- Jam packed with high quality down

- Good enough for Everest and other 8000m mountains

2. Mont Bell Alpine Light Down Jacket – 800 Fill