Main Menu

Tag Archive: winter jackets

  1. Lightweight Down Jacket – Full Zip or Half Zip?

    Leave a Comment
    Lightweight Down Jacket - Full Zip or Half Zip?

    When choosing a lightweight down jacket one of the most important decisions you will need to make is whether to have a full length zip or a half length zip. Both have their advantages and disadvantages, so ruminate on our list before you make a decision.


    Full Length Zip Positives

    Easy to take on and off

    Vent yourself easily if the zip is two-way

    Can be opened out and used as a blanket

    Access inner pockets quickly

    Possible to join it with other jackets

    Full Length Zip Negatives

    Larger zip area leads to greater heat loss

    More surface area for wind and rain penetration

    More wear and tear on the zip


    Half Length Zip Positives

    More down area, so warmer

    Less zip wear and tear

    Better fit around the stomach

    Less zip area for wind and rain penetration

    Half Length Zip Negatives

    More difficult to take on and off

    Harder to access inner jacket pockets

    Harder to vent your body during intense exercise

    Lightweight Down Jacket – Full Zip or Half Zip?

    At the end of the day both half zip and full zip lightweight down jackets are going to keep you warm. The decision you will need to make is do you want a jacket that is versatile – full length zip, or one that is slightly warmer and better fitting – half length zip.

    If are poor at regulating your body heat and are constantly placing on and removing jackets then the full length zip is the style of lightweight down jacket best suited to you. If you feel the cold and very rarely remove a jacket over long periods of time outdoors, then the half zip version is going to be more useful.

    And finally, what about your hair? If you like to look perfect and are constantly preening yourself then a half zip jacket is going to cause you untold grief, so they are best avoided!

  2. Down Insulation Science In Outdoor Jackets

    Comments Off on Down Insulation Science In Outdoor Jackets

    Science Behind Down Insulation In Outdoor Jackets

    What is down?

    Goose down cluster - Image kindly supplied by EDFA European Down and Feather Association

    Down is the fluffy plumage that waterfowl grow next to their skin to help insulate and aide buoyancy. It is not a true feather as we understand them, but a much simpler form that has soft and fluffy filament shafts growing in all directions. These down ‘clusters’ are extremely lightweight and provide a large surface area to trap air and warmth from the body. True feathers grow over the top of the down and help shield the birds from wind and water penetration, as well as aiding flight due to increased aerodynamics.



    Why use goose down?

    All waterfowl produce down, but geese and duck down are the most popular as it is a by-product of commercial farming practices. The most sought after down comes from adult geese as they have a very fine cluster construction, providing more loft than juvenile goose down or duck down.

    Advantages of down insulationDown insulated jacket by Sub Zero

    One of the major advantages of down is its warmth-to-weight ratio. No synthetic insulation even comes close to matching it. So producing a like-for-like jacket, the down insulated one is going to be much lighter than the synthetic insulated one. Combined with this is the compression advantage of down. You can scrunch up down jackets in to very small shapes without damaging the clusters. If you want to wear one that has been jammed in to an awkward shape in yor backpack, just like a duvet, all you need to do is waft it a little bit to increase the loft.

    Negatives of down insulation

    Downs Achilles heal is moisture. If it gets too damp or is waterlogged, then the clusters stick together, drastically reducing the surface area and thus the insulation properties. Drying down takes a very long time unless you have a  tumble dryer, so if it gets wet when you are outside, then it is going to stay wet and offer little protection from the cold. Fortunately, new hydrophobic treatments have started to be applied to down clusters to help repel water for longer. Using this treated down produces an insulated jacket that is not waterproof, but it will function a lot better in damp and wet weather, will dry quicker, and will retain the loft of the down even when wet.


    For more information on down and its properties then please visit the EDFA European Down and Feather Association


Enjoy this blog? Please spread the word :)