Duck, Duck, Goose: A Comparison of Insulations

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Duck, Duck, Goose: A Comparison of Insulations
NEMO Equipment, Inc.
Duck, Duck, Goose: A Comparison of Insulations
The Outdoor Industry uses goose or duck down for natural-fill insulated sleeping bags. Duck and goose can
be equally efficient insulators, and their effectiveness depends more on the fill power, quality of the fill (i.e.
percentage of down to feathers), and processing quality than the source being duck or goose itself.
Figure 1: Note the relative size difference between duck (left) and goose (right)
More than being just as thermally efficient, duck down is more readily available as a consistent source, and
oftentimes more affordable. Since all down exists solely as a byproduct of the meat and egg industries, the
availability of duck down compared to goose down is attributed to greater demand of duck meat and eggs as
a consumable food. Most of the debate centered around duck vs. goose can be addressed by looking at the
myths attributed to the two types of insulation.
Durability
Generally speaking, there is no difference between the durability of duck down and goose down, regardless of
fill power. Part of the durability question revolves around the natural fat and oil content of the down. Some
birds have an inherently higher fat and oil content. Moreover, down is an organic product and will vary season
to season due to factors such as weather, feed, bird condition, etc. The presence of a certain percentage of fat
and oil is required to keep the down pliable and resilient (warmth-trapping).
Figure 2: 850FP duck down cluster (left) and 850FP goose down cluster (right)
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If during processing, down is “over washed” and too great a percentage of fat and oil is removed,
the down can dry out and become brittle, thus making it easier to break down, decreasing fill
power. Ultimately, high quality processors such as those that work with NEMO, individually assess
each batch of down to optimize durability and performance, irrespective of species.
Odor
Down is a natural product, like wool. While a certain percentage of fat and oil is required to naturally keep the down pliable and resilient, the presence of these substances also contributes to the
scent. Those with an acute sense of smell may notice a very slight odor, with even the cleanest
down. Since feeding habits differ between duck and goose, minor differences in odor may arise
between the two species, as the odor is held in the oil content necessary for resilience. One of the
many benefits of DWR treated down, like DownTek™, is the minimization of that odor.
Availability of Higher Fill Powers
Higher fill power down tends to come from older more mature birds. The longer a bird lives, the
more developed the down cluster. Furthermore, to achieve a desired fill power, processors sort
through feather, small down clusters, large down clusters, etc., to make down of a certain content
and fill power.
Figure 3: Large down cluster (left), small down cluster (center) and feather (right)
The current highest fill power for goose is approximately 1000 FP, but this is available in extremely
limited quantities (and usually prohibitively expensive). Comparatively, Eider duck down, the
highest-end most expensive down by an order of magnitude, has been anecdotally rated up to
1200 FP. More common fill powers for duck and goose down range from 450-850 FP. High-end duck
down in 850 FP has recently become more accessible due to improvements in the sorting process
that filters out additional fibers and small down clusters.
NEMO Equipment, Inc.
Color
Both duck and goose down are available in white and mottled grey. Historically speaking, white
colored down has been more desired in the bedding industry because most bedding fabric is
white, and manufacturers prefer to hide the presence of down. Besides a visual difference, there is
no performance difference between white and grey colored down of the same specification.
Figure 4: Grey down cluster (left) and white down cluster (right)
The Takeaway
Duck and goose down can be equally efficient insulators when variables such as fill power, quality
of fill, and processing are taken into account. The quality of down is directly tied to everything from
the feed of the bird during its life, to the length of its life, to the wash method used in processing.
When selecting the best insulation for NEMO sleeping bags, we aim to maximize the comfort and
performance of our innovative bag profiles, while delivering top performance for each intended
use. We take into account construction techniques, model-specific design details, and
material/insulation choices when creating every NEMO sleeping bag.