Four people stood on a log laughing, lake behind

Layers of Escapism: Down vs. Synthetic Insulation

What they are. Why they’re different.

An insulated jacket is a staple for cold-weather roams. For proper off-season travel, hiking and winter escapism, zipped up to the chin with hands stuffed in pockets and beanie centred up top. It’s a matter of down vs. synthetic, each offering pros and cons in jacket form. The type of insulation affects warmth, weight, water resistance, compactness, price, and packability.


So getting to grips with the difference between down and synthetic insulation can be the difference between “stoked on adventure” and “stuff it, let’s head home”. Grab a brew, sit back and let’s get into it.

Two men walking in a forest, smiling in thick jackets

What’s The Difference Between Down and Synthetic Insulation?

Down

We’ve partnered with Downlite®, a world leader in traceable, responsible and welfare-first feather and down supply to introduce down jackets and vests into our range for Autumn / Winter 2024 - The Ashland for men and the Northstar for women. Down jackets are made with the plumage found underneath the outer feathers of waterfowl like ducks and geese. It’s a natural insulator and a by-product of the poultry industry, which means that no birds are raised for the down alone. This is a big part of why we source and process through Downlite®, who trace the fabric through its full journey from start to finish.


The big win with a down jacket is its weight-to-warmth ratio. As a base material, down retains heat remarkably well as it pockets warm air and distributes it around the body incredibly efficiently. This means the jacket can stay super lightweight, as less stuffing is required to achieve the same warmth given by synthetic insulation. For the same reason, they’re a real space-saver in your pack, long-lasting and surprisingly breathable.

A sketch of a down jacket, front
Design team’s early sketches & scribbles
A sketch of a down jacket, back

"We created the Ashland and Northstar 650 fill power down series of jackets & vests as we felt our Roamer needed to have that instant warmth with little weight in their outfitting. These down outerwear pieces layer really nicely with our waterproofs & lightweight fleeces - perfect for all-weather adventuring.”

Sharon, Outdoor Active & Accessories Designer.

The optimal conditions for down being cold and dry—think of northwest USA and mainland Europe. A slight drawback of down insulation is that it struggles to perform in the wet. If you’re hit by a sudden downpour or moisture gets to the insulation, it’ll clump together and fail to retain any heat. Both our Ashland and Northstar have a PFC-free water-resistant outer coating, but this is for initial protection from light rain, mud and snow. It won’t stop prolonged rainfall or heavy showers, which is where synthetic insulation holds up a little better.


From a responsibility standpoint, down jackets last a very long time. They’re an investment piece and if cared for, can last many years of meaningful escapism. Find out how to do just that, here. Journeying under bright skies, breathing cold winter air and crunching frosty footsteps? Reach for down, our warmest packable jackets to date. 

Synthetic Insulation

Synthetic jackets perform similarly to their down counterparts but with man-made insulation in replacement of animal products. At Passenger, we opt for more responsible synthetic materials such as Thermore®, REPREVE and recycled polyester to insulate our jackets. They give us all the technical benefits of polyester (and more) but with a lower footprint. Learn more about responsible materials and why we use them, here.

A man stood in a jacket, lakeside
Featured: Journey Recycled Insulated Jacket

Heat retention and distribution methods are also much the same as down, but the end product is more breathable and of lower cost. That’s why we use synthetic insulation throughout some of our Warm, Warmer & Warmest outer layers. Everything from our Alaska Recycled Insulated Parka to the Ocean Recycled Jacket—made for winter days off-grid, with plenty of styles to suit the occasion.


It’s worth considering synthetic insulation for higher-exertion activities, think hiking, climbing, bikepacking and scrambling in colder climes. You’ll be running at a higher—and more consistent—temperature, so the loss of body heat isn’t going to be much of an issue. As noted, these jackets can better handle moisture. The same PFC-free water-resistant outer coating is applied, so you’ve got that initial protection in place, but they’ll also dry faster and re-loft faster (‘re-lofting’ is the air-trapping ability of the insulation). This is great for hikes when the weather’s a little less predictable or for everyday escapes, off-season travel and time spent on the road through the winter months.

Down Ratings Explained

The ‘down rating’ or ‘fill power’ refers to the down’s ability to loft and trap heat. Science hat on—it’s essentially how many cubic inches of space one ounce of down can fill. An example being 650 fill power (the amount used in our Ashland and Northstar), which means that one ounce of that down fills 650 cubic inches of space. It’s not a need-to-know, industry lingo removed; a higher rating (number) means that less down fill is required to hold the same amount of heat.

A group looking over a map, smiling in winter layers

“With the PFC-free DWR coating, you can roam in light rain and fog without the down getting damp. The high warmth-to-weight ratio is also great for packing - easily stuffing into a pack for trail or travel."

Sharon, Outdoor Active & Accessories Designer.

Our down range sits in the sweet spot of Outdoor Active, settling into the rhythms of the trail and day-to-day errand running as and when needed. We scribbled out our ethos and pinned it to the wall, making sure not to stray from the path: “Passenger products are Made To Roam, thoughtfully designed, sourced and manufactured to leave a smaller footprint”. It’s for the hikers, van-lifers and everyday adventurers, where a down jacket (or vest) will support their take on meaningful escapism. To inspire and enable more people to spend more time connecting with nature, their passions, doing the things they love in the places they love. We’ve listened, taken on feedback from field tests and roamer experience, and created a down range that works for our roamer.

A man in a down vest, hauling logs

What Is Responsibly Sourced Down?

It’s fully traceable and a by-product of the poultry industry, which means that no birds are raised for the down alone. Downlite® are a leader in this space, sourcing the best quality down for outdoor clothing brands and beyond. However, we are aware that it's still an animal product and this doesn’t sit right for some people.


And… we know our community of roamers value people and planet-first thinking, which led to many a heads-down powwow at HQ to see how we could work down into our jacket range. The clear performance benefits of this natural, fully traceable insulator are pretty clear. If you’ve ever zipped up a down jacket, you know what we’re harping on about. But what turned the dial was the responses to our community gear survey, with a clear want for down within our Outdoor Active range. Straight from the source, we took note.

Down vs. Synthetic Insulation

A woman stood on a ferry, binoculars in hand
A man stood on a rocky path, camera in hand

Down Insulation


Pros

  • Higher warmth-to-weight ratio than synthetic insulation

  • Easily compressed and highly packable

  • A down jacket can last decades of adventure, if well looked after

Cons

  • More expensive than synthetic insulation, in most cases

  • Not always hypoallergenic (very rarely an issue)

  • When wet, down loses its insulating power and takes longer to dry


Synthetic Insulation


Pros

  • Higher water-resistance, performing better in wet weather

  • Less expensive than down, in most cases

  • For high-exertion roams; hiking, climbing, scrambling etc.

Cons

  • Loses heat quicker than down insulation

  • Less durable after high frequencies of wear

  • Generally less packable and bulkier than down insulation

How To Care For Down

Enemy number one to down is the dog... their claws, if we’re pointing fingers. But tears are easily avoidable and even easier to patch up. We’re talking general upkeep, washing and reproofing here, which isn’t as daunting as some might think. Add Nikwax Down Wash Direct and Nikwax Down Proof to your cart and avoid conventional detergents which run the risk of water being absorbed into the down jacket. A big no-no, reducing its insulating properties and water repellency. No good when you’re trying to keep warm out on the trails.

A Guide To Washing Your Down Gear At Home:

  • Remove dirt and close zips: Treat any stubborn stains with a bit of neat solution, before washing.

  • Clean the washing machine: Double-check the detergent tray and care label on your gear.

  • Use a Guppy Friend washing bag: This will prevent microfibres and microplastics from getting into our waterways, we’d recommend grabbing one of these to wash anything with recycled polyester or other man-made materials.

  • Wash your down jacket: A max of two jackets on a cold cycle and add your down wash. Avoid bleach or fabric softener, and use a slow spin setting.

  • Tumble dry: With tumble balls on a low setting until any clumps have disappeared. Teasing apart clumps during the drying process will help restore loft to the down.

  • Air dry: For an hour or so, either outside on the line or in a well-ventilated room, out of direct sunlight. Use a clothes hanger when possible.

Note: Do not iron or leave on the radiator as this can damage the down insulation and Durable Water Repellent (DWR) coating.

Three people stood on a ferry, with a tree-lined shore behind

FAQs

Does down lose its warmth over time?

A down jacket can last many years—decades even—of adventure if it’s well looked after. Watch our handy guide to do just that, here. After a long while, down can lose its lofting ability and insulation power but this is dependent on the frequency of use and how much care you invest in the jacket.


Is synthetic insulation better than down?

The type of insulation is very much dependent on the roam, and roamer. It affects warmth, weight, water resistance, compactness, price, and packability. We hope our guide to Down vs. Synthetic insulation can help you make a more informed decision.


Is down warmer than recycled polyester filling?

Down is generally warmer than polyester fill as it has a higher warmth-to-weight ratio, but a recycled polyester filling is more breathable and often cheaper. We offer both types in our range of insulated jackets.


Is a down alternative better than polyester?

Down is a natural insulator, whilst polyester is fully man-made. We use recycled polyester in our synthetic insulated jackets, the great benefit being that it uses materials that might otherwise go to landfill. From a performance standpoint, both forms of insulation offer pros and cons so it’s worth thinking about factors like warmth, weight, water resistance, compactness, price, and packability to get a feel for what’s right for you.


What is responsible down sourcing?

Responsibly sourced down refers to any down that passes the highest animal welfare standards. We source from Downlite® as the raw material is fully traceable and a by-product of the poultry industry, meaning no birds are raised for the down alone. Learn more about Our Materials.


Is it normal for feathers to come out of the down jacket?

Feathers will sometimes come through the seams or fabrics, we use downproof fabrics and constructions to alleviate this as much as possible. But the odd feather will poke through every now and then. It’s completely normal.


How should you store a down jacket?

Don’t forget to unpack your jacket and give it some breathing room. Scrunching, stuffing and squirrelling it away in the bottom of a rucksack will break down the loft over time. It’ll struggle to spring back and deliver on warmth, so hanging on a peg or rail is best practice. 

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