Down Vs. Synthetic

Down vs Synthetic - Which Jacket Is Right For You?

Winter is coming, and now is the time to start thinking about how you’re going to stay warm when the chill really sets in. Whether you simply want a jacket to keep you cosy on your morning commute, or you're after a high performance jacket to battle the elements on a winter expedition, there are a few things you should consider before investing in a new puffer jacket.

Not all puffer jackets (or insulated jackets as we call them in the biz) are created equal, and each type is designed to serve a different purpose. Here at Macpac, we have two kinds of insulated jackets: down or synthetic. There are pros and cons of each. But what you should ultimately choose depends on what you plan on doing in it.

Down insulation

While both technically do the same thing (keep you warm), not all insulation is created equal. Down is no exception, which is why we only use responsibly sourced, RDS duck or goose down in our down jackets. RDS ensures our down comes from humanely treated ducks and geese and helps to provide traceability in our supply chain.

Benefits of Down Insulation

High quality duck and goose down offers the best warmth-to-weight ratio of any insulation. It works by trapping body heat inside thousands of tiny pockets of air, making it perfect for puffer jackets and sleeping bags because it can easily be compressed into small spaces for packing.

Downsides to Down Insulation

Down doesn’t perform well when it gets wet – full stop. The plumules (feathers) clump together and lose their ability to loft (puff up).

One way we get around this is by using water-resistant HyperDRY™ down. Although it’s not completely waterproof, this down is treated with a PFC-free compound that acts in the same way a durable water repellent does; using a short chain of molecules that encourage water to bead and roll away, providing greater water resistance and faster drying times.

There’s also the question, “why don't you just use a waterproof fabric?” But because each baffle needs stitches to hold down in panels across your body, each stitch creates a tiny hole that water can get into. Until now. Shop waterproof down.

In summary, here are the benefits and cons of down insulation:


  • Incredibly warm
  • Superior warmth to weight ratio
  • Highly compressible
  • Long life when properly cared for
  • Renewable resource
  • Conforms to body shape for max comfort


  • Loses ability to insulate when wet
  • Special cleaning requirements
  • Slow drying time
  • More expensive than synthetic
  • Not hypoallergenic

Synthetic insulation

Macpac’s synthetic options replace goose or duck down with PrimaLoft®, an ultra-fine polyester microfiber blend. PrimaLoft® fibers are treated so that they don't retain water, which is why they are able to keep you warm no matter how hard it pours. Similar to down, it works by trapping heat in tiny air pockets.

Benefits of synthetic insulation

PrimaLoft® is incredibly soft, light and warm. It also retains most of its insulating ability when wet. This makes it a better option if you’re expecting moisture, or if you’re adventuring above the snowline.

If ease-of-care is also important, it’s worth considering a synthetic option.

Garments like this, although not quite as warm as premium down-filled jackets, are incredibly easy to care for, and still provide an excellent level of insulation. Unlike traditional down jackets, synthetic puffers aren’t overly compressible, so they won’t pack down as well as a down jacket.


  • Good insulator
  • Retains over 90% of insulating ability when wet
  • Fast drying
  • Easy to care for
  • Vegan option
  • Cheaper than down
  • Hypoallergenic


  • Worse warmth to weight ratio than down
  • Not as durable as down
  • Doesn’t compress well
  • Heavier than down

How to measure the warmth of an insulated jacket?

When comparing the warmth of down jackets, there’s a lot to consider: there’s fit, baffle design and length, just to name a few. At the end of the day, it’s always going to be a trade off between warmth and weight, so before anything else you need to consider the activity you’ll be using your jacket for most. Here, we are going to focus on two factors.

The first is loft

Loft (or fill power) is one measure of down quality. It’s the space in cubic inches that an ounce of down will occupy, and the measurement takes the form of a number – think 600, 750, 800 etc. Macpac down jackets use responsibly-sourced, high-quality RDS goose and duck down with fill powers ranging from 600-800. The higher the number, the more effective the insulation.

The second is fill weight

Fill weight is the actual amount of down inside the jacket. For example, our 800 loft Icefall Down Jacket would be warmer than the same jacket made using 600 loft down, because its higher lofting down means it has a greater warmth-to-weight ratio. However, if it’s compared to another jacket with less loft but more fill, it won’t be the warmer option.

Our Sundowner jacket is a prime example of this. It uses 600 loft down, but because it has 205 grams of fill it’s technically warmer than an 800 loft Icefall — filled with 95 grams (men’s) or 88 grams (women’s, size 10) of down respectively. The trade off, of course, is that the Sundowner is heavier and less packable.

Outer fabric

It’s not just about the insulation itself, but also what it’s encased in. The outer fabric has a lot to answer for – it dictates the entire garment’s performance from durability and warmth, right through to weather resistance.

We use a range of fabrics on our insulated jackets. Our outdoor essentials collection will generally feature classic 100% Nylon Taffeta as found in our Halo and Uber Light Jackets. This is for a more classic look, best suited for wear around town and designed specifically to handle the wear and tear of daily life.

Our technical garments use performance outer fabrics by Pertex®. Jackets like the Sundowner are designed for maximum warmth, weather resistance and durability at minimum weight for harsh environments.

If you’re still unsure about which insulated jacket is the right choice for you, head in store and talk to an expert! Knowledge is power, and they’re more than happy to show you what we’ve discussed. Arm yourself with the tools to make an informed purchase and you’ll be ready to take on the elements for many winters to come.

Shop Insulated Jackets
A guide on picking the perfect puffer jacket. We have jackets for all adventures, from the morning commute on the bike to scaling peaks in the Alps.
5 mins