Down Comforters: What Is Fill Power?

Learn what to know about fill power and how it affects the quality, weight, and warmth of a down comforter. Understand how to choose fill power.

What Is Down Comforter Fill Power?

When shopping for a down comforter, you may have noticed various retailers touting their blankets’ “high fill power.” With so many options already available: queen or king, down or down alternative, baffle box or sewn-through, fill power presents yet another choice when selecting your down bedding. But what exactly is fill power, and will it be an important aspect in your purchasing decision, or just a whole lot of fluff?

Fill Power Explained

Fill power is the unit of measurement for the volume from a single ounce of down, where the higher the fill power, the better the insulation. Basically, the larger the number indicated for the fill power, the warmer the blanket. Interestingly enough, a higher fill power will translate into a lighter comforter, since less overall down must be used.

Therefore, a down comforter with high fill power will keep you cozy and warm without feeling like you’re being crushed under the weight of your blanket.

Types of Down

Down comes from the undercoat of a bird, and is soft and lightweight, yet insulating. Down does not use the bird’s feathers, meaning no stiff, hard or pokey quills should be coming through your comforter. Down typically comes from geese, but can also be used from ducks, although duck down is mainly found in lower end comforters.

Higher end comforters on the other hand often utilize Hungarian goose down, as these birds are accustomed to the cold climates and naturally produce a down coat with the best fill power.

Cluster Size

So what accounts for this variation in fill power? What makes one bird’s down more insulating then the next? It comes down to cluster size, where a higher down cluster equals a higher fill power. As the animal grows, so does its cluster size, which means a larger, mature bird will produce down with a higher fill power than a younger bird.

Aging in the animal kingdom is actually a good thing!

Loft and Longevity

Fill power also effects the down comforter’s loft, or its ability to puff up. In order to reach its maximum loft, a down comforter should have a high fill power paired with baffle box construction.

Baffle box down comforters have tiny fabric strips placed throughout the inside of the comforter that allow the down to be evenly distributed throughout the blanket. This type of construction allows the high fill power down to reach its full loft potential, as well as retain its shape over time.

Low-end comforters tend to eventually go flat, due to the down’s poor-quality fill power as well as the sewn through construction techniques that create pressure points or cold spots on the blanket.

Since pricier comforters utilize high fill power down as well as baffle box construction techniques, these blankets tend to retain their loft and billowiness, thus eliminating the need to replace your bedding every few years. With down comforters, a higher initial investment will end up saving you money over time.

Should You Always Look for High Fill Power?

Now that you know loft, durability, and quality construction are all the results of a high fill power comforter, is there any reason you’d want to avoid this type of bedding? As you would expect, if you’re on a limited budget, high fill powered comforters won’t be your best option as their cost can exceed that of their lower-end counterparts by about $100.

Also, if you’re purchasing a down comforter for a “low-traffic” area, like a guest room, and the bedding won’t see much usage, you’re also better off skipping a high fill power comforter. As all comforters tend to have that plush, billowy look initially, a low fill power down blanket will retain its appearance with only occasional usage, making it a perfect option to bring out those few times a year when Grandma comes to visit.

If you live in a warm climate where there really isn’t much of a winter, and you tend to feel hot as you sleep, you may also want to skip a high fill power comforter, as its insulating ability may be more of a nuisance than a help.

Ultimately whether you opt for a down comforter with high fill power will depend on your individual situation, but now you can rest easy understanding the science behind those numbers.

Resources— Down and Feather Company, Wayfair, Company Store

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