Fabric Definitions — definitions of fabrics, cloths, laces and textile materials from Apparel Search
Down is the fine undercoat of birds under the feathers, and is often used as insulation in clothing. The down of birds is a layer of fine feathers found under the tougher exterior feathers; very young birds are clad only in down. The loose structure of down feathers traps air, which helps to insulate the bird against heat loss — and does the same work inside a jacket or quilt.
Down is the fine undercoat of birds under the feathers, and is often used as insulation in clothing. Mammals have an undercoat called downhair.
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down.
The loose structure of down feathers traps air, which helps to insulate the bird against heat loss. For centuries, humans across the globe have used down feathers for insulation.
In the United States, Federal Trade Commission regulations require that any product labeled "100% Down" must contain only down feathers, while products labeled simply "Down" can contain a mixture of fiber and feathers. In addition, products labeled as "Goose Down" must contain at least 90% goose down, 10% goose feathers. Down insulation is rated by fill power, which is the number of cubic inches displaced by a given ounce of down.
Benefits of Down: Down is warm, lightweight and packable. If well cared for, it retains its loft up to three times longer than do most synthetics.
Negatives of Down: when it is wet, the thermal properties of down are virtually eliminated. Down forms clumps if exposed to dampness or moisture, and will mildew if left damp. In addition, it will absorb and retain odors.
Learn about women's down jackets.
Down insulates the way it does because of geometry, not because the feathers themselves are warm. Each down cluster is a three-dimensional puff of fine filaments with no quill shaft to speak of, and thousands of clusters in a jacket baffle hold a large volume of still air in a very light structure. Still air is the insulator; down is simply the lightest scaffolding known for holding it in a garment. That is why loft — the thickness the fill recovers when uncompressed — is the whole performance story, why fill power predicts warmth per ounce, and why compression is temporary in good down: release the jacket from its stuff sack and the clusters re-expand, restoring the air layer. It is also why baffle construction matters, since any unfilled seam gap is a place where the scaffolding, and with it the insulation, is missing.
Down rewards dry care and punishes neglect in specific, predictable ways. It should be stored uncompressed so the clusters are not permanently flattened, washed only with down-appropriate cleaning and dried thoroughly — mildew follows damp storage, and clumped down must be fully dried and re-lofted to work again. In use, a down garment's shell does much of the weather work: the fill is protected from rain and wet snow by the outer fabric, because the wearer who lets the fill soak loses the insulation exactly when it is most needed. Synthetic fills exist largely as the answer to that single weakness, trading some warmth-to-weight and longevity for insulation that survives damp. Knowing down means knowing both halves of that record: the best natural warmth-to-weight performance available, conditional on keeping it dry.
Fill power rates down insulation: it is the number of cubic inches displaced by a given ounce of down. Higher fill power means the down lofts more per ounce, so a garment reaches the same warmth with less weight and packs smaller — the key quality measure for down clothing and bedding.
Federal Trade Commission regulations require that a product labeled 100% Down contain only down feathers, while a product labeled simply Down can contain a mixture of fiber and feathers. A product labeled Goose Down must contain at least 90% goose down and 10% goose feathers.
It is virtually eliminated. Down forms clumps if exposed to dampness or moisture, the trapped-air structure collapses, and the material will mildew if left damp and absorbs and retains odors. Dry down, well cared for, retains its loft up to three times longer than most synthetics — the trade is durability dry against failure wet.