Understanding Down
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Understanding Down

January 29, 2015

Understanding Down

Down is a tricky business. Where does it come from? What is loft? Is it high quality, is it high loft, is it DWR down?
Knowing about these terms is important when it comes to choosing down products, knowing what sort of conditions they’re appropriate for and knowing whether you’re getting the most bang for your buck.

What is down?

Down is a layer of very soft feathers that grow underneath a birds exterior feathers. Down is extremely lightweight, very soft and is very effective at trapping warmth.

How is down sourced?

The down used in Mont Sleeping Bags and Jackets is sourced exclusively from the food industry.
Mont food industry down is never the product of live plucking.

What is Fill Weight?

This is an easy one, Fill Weight is in reference to how much down is inside.

The Brindabella Standard Sleeping Bag has a fill weight of 680g of down

The Brindabella Standard Sleeping Bag has a fill weight of 680g. That’s 680g of down.

What is Loft or Fill Power?

Loft (or Fill Power) is in reference to the quality rating of the down. Down quality is measured in Loft and Loft is measured by cubic inches per ounce (28.35g). The higher the number, the greater the volume per ounce and the warmer the down will be.

1 ounce of 785+ Loft Down will have a minimum volume of 785 cubic inches and

1 ounce of 850+ Loft Down will have a minimum volume of 850 cubic inches.

The higher the loft rating, the higher the warmth to weight ratio. 100g of 850 loft down has the ability to trap more air, and more warmth, than 100g of lower loft down.

High loft down is able to spring back to its full size many more times after compression than a lower loft down.

When comparing down products between different manufacturers it is important to understand that there are multiple different tests used to grade down. Each of these tests have different procedures and will produce varying results. Mont down is tested using only the IDFB USA Test Method.

Which is better, Duck or Goose?

The quality of down fill and its performance doesn’t necessarily relate to the species it is sourced from. It is true that in the case of extremely high lofting down, loft ratings of 900 and higher, the down is sourced from Geese. But regardless of this fact, an 850 loft Duck Down will be just as warm and have the same weight as an 850 loft Goose Down.

When it comes to bang for your buck, duck down is more affordable than goose down. A sleeping bag with 850 loft duck down will be significantly cheaper and have the same performance as the same sleeping bag with 850 loft goose down inside.

As for differences between grey and white down, those differences are purely cosmetic.

What is Down Ratio?

All down batches will contain some percentage of pin-feathers and down fibres. The higher the down quality or loft, the lower the percentage of pin-feathers and down fibres. Good quality down will generally contain at least 90% down clusters.


All down used by Mont is tested and rated by an independent lab and is guaranteed to be of the highest quality.

DWR Loft: Water Resistant Down

DWR Loft is an environmentally friendly (Blue Sign Certified) down treatment that protects down from moisture, helps it maintain its loft in wet conditions, greatly reduces the drying time, extends the life of the down in your product and improves its resistance to bacteria growth.

Look for the DWR Loft logo on Mont Down Sleeping Bags and Down Clothing.

Caring for your Down Sleeping Bag or Garment

  • To get the most warmth from your sleeping bag it is best to lay it out and fluff it up about 1 hour before going to bed.
  • Body oils, sweat and other contaminants on your body can build up over time on and in your sleeping bag and may damage down clusters. Using an inner sheet or wearing a tee-shirt and underwear in the bag can reduce the amount of these contaminants making their way onto and into the sleeping bag.
  • Between trips always store your sleeping bag or down product loose or in a large storage sack rather than a compression sack. This will help maintain the loft of the down and the warmth of your product.

For more in depth info on caring for your down product see the Sleeping Bag Care Guide

 


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