Down - A Warm & Fluffy Wonder

What is Down?

Down is the soft under plumage (the insulating layer beneath feathers) that geese, ducks, and other waterfowl must keep warm and dry.

Down usually consists of two main types: goose down and duck down. Goose down is larger and softer, while duck down generally has smaller down. But they all have good thermal insulation properties.

Down is used to keep down comforters warm, making them fluffy and comfortable, and as the filling in down pillows, making them stretchy and supportive. Goose and duck down are also used in other bedding products such as feather beds and blankets, as well as clothing such as jackets and gloves.

Selected for its luxurious warmth, softness, superior resilience, loft and thermal properties, goose down is unmatched by synthetic fillings.

What is filling power?

Fill power or "loft" is how the quality and size of down tufts are defined. The larger the down tuft, the higher the fill power rating, which is the number of cubic inches an ounce of down will fill under specific laboratory test conditions.

For example, 1 ounce of 800 fill power will fill 800 cubic inches of space, and 1 ounce of 900 fill power will fill 900 cubic inches of space:

Quality Down = Long Lasting Comfort & Resilience

Fill powers range from 300 cubic inches per ounce to 800 cubic inches per ounce and above for the highest quality down. The Feather has no padded power rating.

For a down comforter: A good quality duvet with large down will make you more comfortable, i.e. warmer when cold and cooler when warm than lower quality down. For down pillows: Higher quality down will produce a fluffier, more bouncy pillow than lower quality down.

Reduce cluster density and adhesion

Filling power is important and it's on everyone's radar because it's relatively easy to measure and quantify. However, "density" and "adhesion" are at least as important when evaluating the highest quality down.

Density is an attribute of mature down. Mature down tufts with a denser center will insulate better and be more "resilient" than immature down tufts of the same size.

Lower clusters with the same filling force. Mature clusters are denser and of better quality

What is the down fill weight of a duvet?

Don't confuse fill weight with fill power! Fill weight is the actual weight of a duvet's filling. The higher the fill weight, the heavier the duvet will be. However, a thick duvet does not equal a warm duvet.

Fill weight determines how soft or firm a duvet is, but fill power measures the effectiveness and quality of a duvet or duvet's filling. Therefore, a duvet with a high fill weight and low fill power will be heavy but less warm.

What Fill Weight Means - If you see a weight quoted in "gsm" it means the fill weight to one square meter.

Conclusion

Down is popular for its excellent thermal properties, lightness, softness and breathability, making it a popular choice especially in colder climates.