What does down fill power tell us?

Fill power is the measurement for the amount of space one ounce of down takes up. It is the best quality indicator for down, so you can typically find fill power listed on higher end comforters. It’s important to know that down fill power does not tell us how warm a comforter will be because there are too many other factors affecting warmth, including how much down fill is in the comforter. Formulas below help us better understand the relationship between fill power and the weight of down fill.

• Warmth level of a 800 fill power comforter with filling weight 40 oz = Warmth level of a 400 fill power comforter with filling weight 80 oz
• Warmth level of a 800 fill power comforter with filling weight 40 oz > Warmth level of a 400 fill power comforter with filling weight 40 oz

Five Facts on Fill Power

For a given weight of down:

1. The higher the fill power the higher quality your comforter/pillow will have;
2. The higher the fill power the higher your comforter/pillow will loft;
3. The higher the fill power the longer it will maintain its loft and firmness;
4. The higher the fill power the more air your comforter/pillow traps;
5. The higher the fill power the better the insulating power will be;

Down Fill Power and Synthetic Fills

As is well known, down is warm but doesn’t do well in wet and humid conditions. Synthetic fills are designed to replicate the qualities of down, but retain them even when wet. Synthetic fills have no equivalent test to down fill power, and different synthetic fills have different characteristics. So it’s impossible to measure any synthetic' insulation efficiency  using down fill power.

Summary

Although fill power is an important factor you need to take into consideration when purchasing a comforter, there are varied sides you also need to refer to. Its size, weight, thread count, construction, design and so on. All these make a difference on your way to a great night's sleep.