I only own Arc'teryx and Patagonia insulated jackets.
Below are the best insulated jackets in the market. Regardless of price.
As long as your expectations are in the right place, none of them will disappoint. They're all fantastic items.
It makes sense to cover the best uses of these jackets in 5 groups.
- Arc'teryx Nuclei (aka FL), Nuclei SV, Patagonia DAS, DAS Light: Stunning warmth at an instant and incredible wind resistance. Horrible breathability and abrasion resistance. These are all belay jackets. They're primarily meant to maintain your core temp when you stop moving. But I use it casually around town all the time - as long as my output is none to very, very low (not even power walks longer than 5 mins). Otherwise I sweat like a pig in them.
- https://arcteryx.com/us/en/shop/mens/nuclei-hoody
- https://arcteryx.com/us/en/shop/womens/nuclei-fl-jacket
- https://arcteryx.com/us/en/shop/mens/nuclei-sv-parka
- https://arcteryx.com/us/en/shop/womens/nuclei-sv-parka
- https://www.patagonia.com/product/mens-das-belay-parka/85350.html
- https://www.patagonia.com/product/womens-das-belay-parka/85355.html
- https://www.patagonia.com/product/mens-das-light-belay-hoody/85300.html
- https://www.patagonia.com/product/womens-das-light-belay-hoody/85305.html
- Arc'teryx Proton Heavyweight and Atom Heavyweight (aka AR): Perfect picks for cold weather. I'd get the new Proton Heavyweight (breathes more, offers much more pockets, and more abrasion resistant). If you'd like to maximize warmth & wind resistance and can ditch everything else in return, then get an Atom Heavyweight. The Atom Heavyweight is now the Atom SV and we have a new article to take an in-depth look at Arc'teryx's most insulated synthetic jacket.
- Arc'teryx Proton (aka LT), Atom (aka LT), Patagonia Nano Air: Absolutely the most versatile and popular picks. All are perfect for high output activities and casual use at the same time. Proton offers a bit more abrasion resistance. Atom offers a bit more breathability. Nano Air is the only packable one.
- https://arcteryx.com/us/en/shop/mens/proton-hoody
- https://arcteryx.com/us/en/shop/womens/proton-hoody
- https://arcteryx.com/us/en/shop/mens/atom-hoody
- https://arcteryx.com/us/en/shop/womens/atom-hoody
- https://www.patagonia.com/product/mens-nano-air-insulated-hoody/84367.html
- https://www.patagonia.com/product/womens-nano-air-insulated-hoody/84268.html
- Patagonia Nano Puff and Micro Puff: Perfect for 90% casual 10% active use. Preppy, classical family photo look. Packable, cozy and comfy.
- Arc'teryx Proton Lightweight (aka FL) and Atom SL (soon to be called Lightweight): Perfect for high output activities and casual use during chilly spring and summer mornings. Proton Lightweight offers a bit more abrasion resistance and one more pocket. Atom SL is more of an all rounder, offers a bit more breathability and is very slightly insulated, only in the body and nowhere else.
I'll just leave this here... https://arcteryx.com/us/en/shop/jacket-finder/.
Parkas like Therme (Men's - read review) and weighty jackets like Jackson Glacier (Men's - Women's - read review) do not take place in this review.
| Insulator | clo/oz/yd2 |
|---|---|
| 850+ Fill Down | 2.53 |
| 800 Fill Down | 1.68 |
| 650 Fill Down | 1.00 |
| Primaloft Gold aka | 0.92 |
| ⠀ Primaloft Gold Insulation Eco | 0.92 |
| ⠀ Primaloft One | 0.92 |
| 550 Fill Down | 0.85 |
| ⠀ Primaloft Black aka | 0.85 |
| ⠀ ThermoPlume | 0.85 |
| ⠀ ThermoBall | 0.85 |
| PlumaFill | 0.85 |
| Coreloft aka | 0.82 |
| ⠀ Climashield Apex | 0.82 |
| Primaloft Sport | 0.79 |
| Primaloft Synergy | 0.79 |
| Climashield Prism aka | 0.76 |
| ⠀ ThermaTek | 0.76 |
| Exceloft | 0.68 |
| Primaloft Eco | 0.68 |
| Primaloft Silver | 0.68 |
| Primaloft Black | 0.65 |
Sources: Richard Nisley's "A Revised Paradigm for Understanding Garment Comfort Limits" paper, Hohenstein Institute's Primaloft Thermal Performance paper and Primaloft fact sheets (Gold Eco, Silver, Black).
Read more at https://outdoorcrunch.com/clo-values/.
The lighter the Atom jacket (going from left to right in the image), the bigger these panels become. View them both externally and internally for Atom and Atom Lightweight.
These give the Atom line a serious edge when you crave more breathability. With the only exception being the Atom Heavyweight. Because its side fleece panels don't only come with a small area (only around the armpit, see image), but they're also less air permeable.
Best Insulated Jackets: Packed sizes
Arc'teryx's Proton and Atom lines do not stuff into themselves. Nuclei line does. Patagonia's all jackets in this round up do pack into themselves.
Compared to Patagonia's packing system, packing system of Arc'teryx's Nuclei is easier and better for the insulation capability in the long term.
Nuclei line (for example, Nuclei SV, see image), comes with a stuff sack attached and resting inside one of the dump pockets. After stuffing the jacket inside it, the drawcord is pulled to tighten and cinch it.
Patagonia's packing system (for example, Micro Puff, see image), on the other hand, is different. Each Patagonia jacket packs inside one of the pockets (it's either one of the hand warmers or chest pockets). The pocket that is used for packing offers zippers on both sides.
The zip on the other side of the pocket (i.e inside the pocket) is zipped when the packing is complete.
Although I like the packing system of Arc'teryx's Nuclei line, Patagonia's packing system works well too. But there are a few exceptions you should consider:
- DAS Light: Difficult to pack on your own. After stuffing the jacket, it's hard to zip and complete the packing because the jacket overflows and gets in the way of the zip. Try sticking the pack between your legs. This way you can use both of your hands for packing. But even after the packing is complete, there are some things I'd recommend you to pay attention to. The packed jacket must stay away from getting in contact with sharp objects or laying under heavy objects. Otherwise the pack might pop.
- Nano Puff: Smaller zipper pulls make it difficult to pack and unpack with gloves. Definitely not equally as much of a problem of DAS Light though.
Besides these two, packing process of all the other Patagonia items work just fine.
By the way, Arc'teryx revised men's fit for Winter 2024.
Canberk is 5'11" and 165 pounds, with an athletic build. Size Medium fits him perfectly across almost all brands and product lines.
Understanding the Working Principles of Synthetic Insulated Jackets
When it comes to evaluating the end warmth of a synthetic insulated jacket, the amount of insulator is much more decisive than the type of insulator (Coreloft, Primaloft, etc.) that is used.
The warmth difference between different synthetic insulators nearly corresponds to the difference between a 625 FP down and a 650 FP down.
Compared to down jackets, evaluating the potential warmth of a synthetic insulated jacket is a bit more difficult.
To see why, first we need to take a look at the following question:
How jackets provide warmth?
I mean like, why do we even feel warmer when we wear it?
Let's say I laid my insulated jacket over a table. Would my jacket heat that table too?
Well, the answer is no.
The jacket would heat my body, but not a lifeless object, like a table.
That's because jackets provide warmth by preventing the heat from escaping the body it encloses. As long as the body generates and distributes heat, such as a human body or a lizard body like Mark Zuckerberg's, a jacket can heat it. For other inanimate objects like a table, that's not the case, because they don't distribute heat.
This law applies to both down jackets and synthetic insulated jackets.
Down jackets use down (e.g fill) to prevent the heat from escaping the body. Synthetic insulated jackets use synthetic insulators for this.
Unlike down, which is collected from ducks and geese, synthetic insulators are artificial pieces, manufactured inside the laboratories. They imitate the working principles of down.
Most popular examples to these are Primaloft and Coreloft. Primaloft is used by many brands; including Patagonia, Moncler, and Adidas. Coreloft, however, is Arc'teryx's very own, exclusive product that does not take place in other brands.
Remember where I said evaluating the warmth of down jackets are easier compared to synthetic insulated jackets? Well, I actually lied there to get your attention, ha-ha, jokes on you.
Kidding.
The reason that's the case is because we can express them in numbers. We can easily infer the potential warmth of a jacket by multiplying these two numbers: Fill power and fill weight. Fill power represents the heat trapping capability of one unique piece of down. Fill weight represents how much of that fill takes place.
For example, 10 grams of an 600 FP down will most likely provide more heat than 5 grams of 800 FP down. Because 6000 > 4000. Although exceptions exist, this calculation method mostly works.
For synthetic insulated jackets, however, it usually is not that easy. Because the brands usually don't disclose the numbers. There is, however, one parameter we can take a look at.
CLO values
CLO value refers to the thermal insulation provided by any clothing. It is not exclusive to synthetic jackets. Down jackets have a CLO value, too. It is not exclusive to jackets in general either, any clothing can and will have a CLO value.
CLO value is determined by every single thing that impacts the end warmth; like the type and amount of the insulator, the distribution of the insulator throughout the clothing garment, the seams of the jacket, the fit, the length, how much of your body it covers, and so on.
The term "CLO" comes from the word "clothing".
Naked body, for example, has a CLO value of 0, as you would expect. Put on your shoes only, and the CLO value increases to 0.02; contrary to your self respect which plummets while sitting there like a baby flamingo. Wear "walking shorts, short-sleeved shirt", and the value shoots up to, let me check out the ASHRAE Handbook where these standards are listed, to 0.36.
You get the picture.
Also, a CLO value of 1 represents the CLO value of the amount of insulation necessary to keep a resting person in thermal equilibrium in an indoor, normally ventilated (.1 m/s air movement) room with a temperature of 21 deg C (70 deg F).
But wait a second, I certainly would not feel cold if I were sitting naked at 70 deg F. Then why would this scale point that I'd need extra clothing?!
Well, because this scale does not necessarily refer to thermal comfort. It rather refers to a state where heat loss is equal to heat production, and hence the body is in thermal equilibrium with the environment. Since the body temperature of humans is higher than 70 deg F, in order to establish thermal equilibrium, one would need extra clothing.
Anyways...
One of the takeaways here is this: If a jacket has a high CLO value, it means it's good at trapping your body heat and keeping you warm. If it has a low CLO value, it means it's not as effective at keeping you warm.
Like I said, to determine the CLO value of a jacket, one might have to consider factors like the insulation material used, the thickness of the jacket, and how tightly it fits the body. Given the right amount of thickness, any insulator can achieve desired CLO value. It's just going to end up being heavier.
Primaloft vs Coreloft vs Down
A quick recap here: As you see, synthetic insulators lose minimal insulating power when they get wet. Down, on the other hand, loses a lot of it. Biggest reason I mostly recommend synthetic jackets over down jackets.
Now, going back to where I said down jackets also have a CLO value... Let's take a look at CLO values of down with different fill power:
- 550 FP down: 0.70 clo/oz/yd2
- 650 FP down: 1.00 clo/oz/yd2
- 800 FP down: 1.68 clo/oz/yd2
- 900 FP down: 2.53 clo/oz/yd2
And so on.
Now let's take a look at the CLO values of popular synthetic insulators (in dry condition):
- Primaloft Gold (aka Primaloft One - developed by Primaloft and partnered by many brands such as Patagonia, Moncler, and Adidas): 0.92 clo/oz/yd2
- ThermoBall (developed by The North Face): 0.85 clo/oz/yd2
- PlumaFill (developed by Patagonia): 0.85 clo/oz/yd2
- Coreloft (developed by Arc'teryx): 0.82 clo/oz/yd2
Source: Hohenstein Institute and Richard Nisley's "A Revised Paradigm for Understanding Garment Comfort Limits" paper.
As you see, the difference here is smaller.
And we're not even accounting for the fact that higher FP down tends to be distributed more evenly throughout the jacket, and hence becoming even a stronger factor when determining the end CLO value of a clothing. Even besides CLO, higher FP also means a longer lasting product.
- Read more about CLO values: https://outdoorcrunch.com/clo-values/
So, synthetic insulators like Coreloft and Primaloft are much more alike than different. The warmth difference between them nearly corresponds to the difference between a 625 FP down and a 650 FP down.
Which pretty much means that when it comes to the end warmth of synthetic insulated jackets, the amount of insulator is much more decisive than the type of insulator that is used. This is the overarching point of this chapter.
That's why when evaluating the end warmth (e.g CLO value) of these jackets, insulator capabilities are not the only aspect taken into consideration, as that would yield incorrect results and hence be misleading, especially for synthetic insulated jackets.
Check out our other content on jackets:
Guide: Insulated & Shell Jackets
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