Our Guide to Down Jackets

Our Guide to Down Jackets

  • 08 April 2019
  • |
  • First Ascent

Going on a hike, planning an expedition or commuting during winter, wherever and whatever your activity, the First Ascent down range will equip you. For years we have performance tested and improved our down designs, continuing to myriad downs unique properties, to deliver a range which suits every activity in any environment. So when sourcing a down jacket this winter, use this guide to pick the right one for your adventurous lifestyle. 

First Ascent - Our Guide to Down Jackets


Down, the layer of feathers found closest to the birds body, is a natural insulator considered the warmest, lightest and most popular insulator globally. Down insulation features a high warmth-to-weight ratio, trapping the body’s heat, and ensuring minimal heat loss. Down garments are extremely comfortable and versatile and have become the most sought-after garments when braving the winter chills.


At First Ascent we are committed to developing garments which are designed and developed using fabrics and insulators which are ethically sourced, upholding our environmental responsibility and the welfare of animals. Down is used across our down Jacket range, as well as sleeping bags due to its high insulation properties and warmth-to-weight ratio. In 2017 we partnered with the International Textile Exchange, a body committed to minimising and reversing the negative impact which the Textile Industry has on the environment.

First Ascent - Responsible Down Standard Logo

The Responsible Down Standards (RDS) was launched through the Textile Exchange to ensure that all down and feathers bearing the RDS logo are sourced from animals which have not been subjected to any harm, such as live plucking or force feeding, giving fowls the freedom to roam around and live within a free and healthy lifestyle.

RDS certified down provides us with a traceability platform within our supply chain, assisting us with tracking and validating the authenticity of down from farm to garment. Each step of our Down supply chain is certified by an approved third-party, whom ensure each farm/factory is audited and uphold the standards set by RDS.
Read more on RDS here: http://responsibledown.org/



Fill power is the international rating system used to measure the loft and the relative quality of the down used in the garment. This number is calculated based on how much space one millilitre a down cluster takes up in a cylindrical tube.

Fill-power can range from 550 to 900 fill; this number highlights the cluster size, which refers to the amount of body heat that the down is able to trap relative to its loft. Fill Power does not determine the amount of down utilized in a product, however the higher the loft the more body heat is trapped and the more compressible the garment is.

At First Ascent our down jacket's feature a fill power of 600 to 650, this fill power ensures ultimate warmth whilst still providing compressibility.

First Ascent - Our Guide to Down Jackets


The fill weight of a garment represents the amount of down which the garment holds, this number is measured in grams in South Africa. The more down which the garment holds, the warmer the garment will be.


Look out for the fill ratio when purchasing your next down garment. This information is an indicator representing the make-up between soft down and the harder down feathers.

A garment, which features a higher percentage, for example 90/10, is warmer, lighter and more easily compressible garment, as it features a high percentage of down (90) to feathers (10).

First Ascent - Our Guide to Down Jackets


Nothing can compare to the insulating properties of down, however when it comes to moisture, down naturally absorbs, causing its insulating benefits to fall away. When moisture is absorbed into the down fibres, down filaments will stick together, creating gaps for cold air to penetrate and hot air to escape.

To lessen this effect, all First Ascent down jackets feature a hydrophobic DWR coating, which aids in repelling water from the jackets surface. This coating does not make the jacket waterproof, and would require an outer shell in order to be worn in rain conditions.


Majority of down allergies which occur are as a result of improperly cleaned down. Down, being a natural product can be a breeding ground for dust mites, mold etc. which are the main cause for allergies arising. 

At First Ascent we take great pride in ensuring that our down surpasses all cleanliness tests to provide garments which are hypoallergenic.

First Ascent - Our Guide to Down Jackets


The construction of a down jacket referes to how the down jacket was made up. Down jackets are constructed from a series of baffles - individual chambers which hold the down in place to ensure even distribution of down across the garment. Baffles are what give every down jacket a different appearance.

We utilize two types of construction in our down range, namely stitch through and bonded baffles.

First Ascent - Our Guide to Down Jackets

Stitch through

Stitch through down jackets such as the Transit Down, have been constructed by stitching the outer fabric, directly to the inner fabric. This construction allows for less outer fabric and stitching to be utilized, in turn making the garment more lightweight.

Seal baffle construction

The seal baffle construction method is used in our Down Seal Jacket. Created using a specially made jacquard loom, the jacket’s face, back and baffles are woven simultaneously as a single fabric. This seal baffle construction eliminates the down from migrating, cold spots from forming and water from penetrating into the down insulation, making this jacket ideal for skiing and snow adventures. The removal of glue and intricate stitching makes seal jackets warmer, durable and more flexible.


Lightweight: 50 - 100g

Transit Down Range

Designed for hiking, travelling and outdoor adventures where every gram matters, the Transit Down Jacket is our lightest down jacket in our range. Featuring a 650FP and a 90/10 down ratio, this down jacket is packable into its pocket, making it the perfect stuff-and-go travel companion. Lightweight down jackets are ideal layering pieces, as they provide a great warmth-to-weight ratio and are easy to transport around when weather in unpredictable and where layers may be required. 

  • 650 fill-power and 90/10 down ratio
  • Responsible Sourced Down (RDS)
  • Packable into pocket
  • DWR coating to aid with water-repellency
  • Hypoallergenic quality down
  • Adjustable hem cord to ensure the perfect fit
  • Interconnect zip compatible system for layering
  • Wind stop zip baffle
First Ascent - Men's Transit Down Jacket First Ascent - Ladies Transit Down Jacket First Ascent - Men's Transit Down Hoodie
Men's Transit Down Jacket Ladies Transit Down Jacket Men's Transit Down Hoodie
First Ascent - Junior Transit Down Jacket First Ascent - Men's Transit Down Body Warmer Vest First Ascent - Ladies Transit Down Waistcoat
Junior Transit Down Jacket Men's Transit Down Body Warmer Vest Ladies Transit Down Waistcoat

Mid-weight: 100 – 150g

Jackets and Parka's

Whether you are heading out to the slopes or just trying to stay warm in the cold weather, the Down Seal Jacket will be your go-to jacket. This jacket has a higher fill weight, making it puffier than that of a lightweight down, providing more warmth but less compressibility.

Features Down Seal: 
  • 600 fill-power and 80/20 down ratio
  • Responsible Sourced Down (RDS)
  • Bonded baffles for greater warmth and durability
  • DWR coating to aid with water-repellency
  • Stuff bag
  • Adjustable hem cord
  • Wind stop zip baffle
Features Arctic Down Parka:
  • 650 down-fill Power and 90/10 down ratio
  • Inner lycra cuff with thumb loops
  • Two way zipper for temperature control
  • Media compatible inner chest pocket
  • Generous down filled hood
  • Feminine tailored fit
First Ascent - Men's Down Seal Jacket First Ascent - Ladies Down Seal Parka First Ascent - Ladies Arctic Down Parka
Men's Down Seal Jacket Ladies Down Seal Parka Ladies Arctic Down Parka

Expedition weight: 150 – 300g

Glacier and Extreme Glacier Down Jacket

When looking for expedition outerwear these are the jackets you’ll need. Expedition weight, down jackets are the warmest jackets on the spectrum and feature the greatest fill weight. These jackets feature heavier duty outers on selected area or on the full outer, to provide increased durability on expeditions. A water-resistant outer is an added benefit on selected expedition down jackets.

Features Glacier:

  • 650 fill-power and 90/10 down ratio 
  • Responsible Down Standard (RDS)
  • Hypoallergenic down
  • DWR coating to aid with water repellency
  • Adjustable hem drawcord
  • Anti-scuff elbow pad
  • Wind-stop zip baffle
  • Chest pocket for additional storage

Features Extreme Glacier: 

  • 650 fill-power and 90/10 down ratio 
  • Responsible Down Standard (RDS)
  • Hypoallergenic down
  • Microtex outer and inner fabric
  • Durable taslan protects shoulders and sleeves
  • Anti-scuff elbow pads with gussets and velcro cuffs
  • Four exterior pockets and an internal pocket
  • Zip removable down filled hood

Features Malamute Down Jacket: 

  • Shelled in Vapourtex breathable waterproof fabric
  • Waterproof zippers for increased protection
  • Optimally filled with premium quality goose down for ultimate insulation
  • Zip removable hood with volume adjustmen
  • Two chest pockets and two handwarmer pocket
  • Accessory D-loops for attaching gloves

First Ascent - Glacier Down Jacket First Ascent - Men's Extreme Glacier Down Jacket First Ascent - Malamute Down Jacket
Glacier Down Jacket Men's Extreme Glacier Down Jacket Malamute Down Jacket