Duck, Duck, Goose: A Comparison of Insulations
Transcription
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) NEMO Equipment, Inc. 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.