Fill-power is the key to luxury
Down is the soft undercoat beneath the birds’ feathers, found mainly on the belly and breast. The more air down is able to trap, the greater the loft (springiness) of the down. The quality of down products varies, so, having decided to purchase a lovely down sleeping set, you need to be aware of the factors that influence the end product.
What is fill-power?
Fill-power indicates volume; the number of cubic inches occupied by one ounce of down. Higher fill-power means larger, fluffier and denser down, providing better heat modulation (warming and cooling) while also being lighter in weight as fewer feathers are used.
A high fill-power does not mean warmer, heavier or thicker. It means airier, loftier, softer with the promise of keeping your body at a nice, even temperature and perspiration-free all night. Fill-power is a measure of quality.
Fill-weight is a different matter. It signals quantity, the actual weight of the duvet filling. It determines how soft or firm, light or heavy a product is. TOG is another matter, used to measure the warmth of all materials, including down.
If you’re used to a more voluminous, heavy duvet, your first experience of Norvegr may be surprising. Our duvets are unbelievably light because of the high fill-power. But after a night or two of perfect sleep, you’ll be addicted. Densely filled duvets cannot provide the harmonious balance between warming and cooling that down does. In fact, thicker, heavier varieties are often poor quality, as they’ve been filled simply to add bulk.
What level of fill-power should I buy?
When shopping for a good duvet, the key is to always choose the highest fill-power of down you can afford – and then some. Your duvet should be just warm enough, but no more. Norvegr offers each customer a sleep consultation to discuss their sleeping environment to decide their perfect fill-power and weight.
The higher the fill power of the down the better the balance it provides between insulation and breathability. That means, you get value for your money when choosing a higher fill power over a lower one. The product is also lighter the higher the fill power, which makes for a duvet that feels like sleeping inside a warm cloud.
The EU fill power scale goes from 0-900. The most common down products have a rating of 400 to 500. These are considered to be low quality, however, as they come from immature geese and ducks with smaller down clusters.
When purchasing a high-quality down duvet, you should look for a fill power rating of at least 600. Down with a fill power of 800+ (EU) is extremely good. 850 is the highest quality that is consistently available. 900 (EU) and above is the very top end of the scale where you find only non-commercially available down types. Our Premium Plus and eiderdown are such qualities. Norvegr’s entry-level duvet collection is the Classic Collection, with a fill power of 755.
Transatlantic fill-power conversion
There are two main systems: European and American. Both use the same basic measuring technique but yield different results due to variances in the test equipment. The US test gives a number that is roughly 7-8% higher than the EU figure for an identical sample. Norvegr products are always listed in EU figures.
Fill power ratings aren’t left to chance. Value is calculated by measuring how many cubic inches a fixed amount of down creates at its maximum loft. To achieve this, the down is put into a Plexiglas cylinder and slightly compressed with a weight.