Prometheus Design Werx


DOWN 101



Down as we know it in the outdoor industry is the layer of fluffy plumage under the outer feathers of ducks and geese. Down has a 3D structure without the stiff quills as found in feathers, and has small filaments growing in all directions. It is this down that traps air molecules in tiny pockets, creating a highly effective thermal barrier. There are approximately up to 2 million filaments per every ounce of down trapping air in these tiny pockets.


The thermal efficiency, warmth to weight ratio, and compressibility when used as an insulating material in outdoor apparel has yet to be replicated by any synthetic insulations. Duck and goose down are warmer than any known synthetic insulations.



Australian chemist and alpinist George Finch is credited as the creator of the first down coat used as a technical, outdoor garment, and commissioned one to be used on the British Everest Expedition in 1922.


Second from the left in the front row, George Finch can be seen wearing his unique and distinct down coat in contrast to his mountaineering peers who all wore their English wool tweeds and gabardines. (Of note, is George Mallory sitting to the left of Finch on this 1922 British Everest Team.)


The modern quilted down jacket with stitched baffles as we know them today from any number of brands and used across many of today's outdoor pursuits, can all trace their origins to American Outdoorsman, Eddie Bauer, yes, that's the Eddie Bauer (brand) we know from the outdoor marketplace. The distinct stitched baffled down jacket was patented in the US by Eddie Bauer in 1940.


Google Patents


Without getting over-technical, "fill power" for down is a relative measure of the loft or "fluffiness". Basically, the higher the fill power, the more air a certain weight of the down can trap, and higher insulating properties the down will have. The better the fill power, the fluffier, lighter and warmer it is as an insulating material.

For examples of measure:

  • 1 oz of 600 fill power down will loft to 600 cubic inches.
  • 1 oz of 700 fill power down will loft to 700 cubic inches.
  • 1 oz of 800 fill power down will loft to 800 cubic inches.

Generally it is considered that 800 fill power down is the start of the "excellent range", and tops out at a 900 fill power.



Performance-wise, there is no measurable difference between duck and goose down until you start getting into the middle 800 fill power range. It is here where only geese can produce the larger size down clusters achieving 850 to 900 fill power ratings.



There is no performance difference between gray and white down. They are the same in every way except for color. It does require more sorting to select white down clusters and really best suited to be used in garments or quilts that uses shell fabrics are light in color so the down color does not show through. It is a cosmetic consideration only.



NO, down jackets were never intended as a rain jacket. The uninformed tenderfoot or urban-only dweller can often been seen wearing their designer brand down jackets in the rain. Don’t do it, you’ll render the down jacket useless and you look like a fool. Plus if it is over 55º do you really need to wear an alpine style mid-layer on some city street?

The one Achilles heel of down is water. Wet down becomes worthless when soaked and all of its fantastic insulating properties becomes moot. Without an ability to trap air, wet down loses its thermal properties.

Enter the next generation of technical, treated goose down where a process is applied to coat each down cluster filament, where the down becomes hydrophobic, repels water and therefore retains its air trapping, superior, insulating capabilities. This unique, technical process to treat goose down does not increase any weight, reduce compressibility, and stays drier 27 times longer than regular goose down.

PDW uses state-of-the-art, next generation of performance, technical goose down.


Quality down jackets all share the virtue of exceptional warmth and a "feather weight" feel while worn. This class of technical mid-layers have mass appeal because in cool and cold weather they simply keep you the warmest with the least amount of felt weight. In the wilderness that means you can go fast, go light, be unencumbered, are protected from the chill, and packs down small to stash in any pack. Originally introduced for alpinists and remains a favored technical mid-layer to this day for their superlative properties in a variety of pursuits in the backcountry.


With today’s advancements in water repellent finishes and treatments, down jackets can be worn longer, in a wider variety of elements and still shine with its natural characteristics. Again, just remember down jackets are still not rain jackets. Today’s DWR treated shells in the best categories of these mid-layers allow the user enough time to shed initial rainfall, grab the waterproof shell to wear over and get back to it.

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