Insulation

Like a whale’s blubber or a polar bear’s thick fur, you’ve got to add insulation to your layering system to stay warm. The last couple of decades have seen vast improvements in both shell fabrics and insulating materials. Synthetic insulation has improved warmth, lighter weights, and less mass, lessening the performance gap between it and natural down. Down has become available in more and higher fill powers, with new hydrophobic technology its performance in moist environments has vastly increased.

The warmth to weight ratios on these cutting edge insulating garments are incredible. I remember the 20 ounce fleece I used to bring along on all my Boy Scout camping trips, and it’s no wonder my pack was always pushing 40 pounds.

One downside: cutting edge comes with a cost; insulation is easily the most expensive clothing category to upgrade.

 

The following are the stats and my humble opinions of insulating layers that I’ve used or researched and wish to use:

 

Montbell Plasma 1000 Down Jacket – $329

montbell-plasma-1000

Weight: 135 g / 4.8 oz.
Fabric: 7-denier Ballistic Airlight rip-stop nylon
Insulation: 1000 Fill Power EX Down
Fill Weight: 1.6 oz.
DWR: Standard DWR treatment
Compressed Size (approx): 3.9 x 5.5 in. / 10 x 14 cm

  • Sewn thru construction
  • Elastic cuffs to seal out drafts
  • No hand pockets
  • Stuff sack included

When I discovered a down jacket at this weight, I just had to have it even though I was skeptical about the durability of such a delicate piece of clothing. Now, almost 5 years later, I can say my worries were unwarranted.

Not only was this the only insulation I took on my 2017 Florida Trail thru hike, but I purchased it 3.5 years before I ever left on that trip, using it almost daily, wearing it around town. Since completing the ‘FT’, I continue to use it almost daily in cold conditions. The extremely light 7D nylon is incredibly durable. I have had a large dog jump up on me and leave deep red abrasions with its claws on my skin beneath this jacket, with zero impact to the jacket fabric itself. During my thru hike, it deflected numerous branches and briers and emerged looking almost new.

I will say that over the years and especially during the extended use of a thru hike, the super light and delicate 1000 fill power down does have a tendency to shift in the baffles and create cold spots. Obviously, I never expect my back to be super warm when wearing down under a pack, because of compression’s effect on down, but the ‘1000 fp’ down compresses so much, you may as well be wearing a jacket with no insulation on the back panel.

Even so, the fragile seeming down is very resilient. Anytime I begin to notice loss of loft, a quick hand wash with a down-specific detergent, adequate drying time, and a good fluffing bring this garment back to almost brand new condition.

 


 

Montbell EX Light Anorak Down Hoody – $269

montbell-ex-light-anorak

Weight: 177 g / 6.2 oz.
Fabric: 7-denier Ballistic Airlight rip-stop nylon
Insulation:
900 Fill Power Ex Down
Fill Weight: 2.3 oz.
DWR: Standard DWR treatment
Compressed Size (approx): 4.1 x 6.6 in. / 11 x 17 cm

  • Sewn through construction
  • 13.4 in (34 cm) half zip
  • Elastic cuffs to seal out drafts
  • Single non-zippered thru-pocket
  • Adjustable hem to conserve body heat
  • Stuff sack included
  • Simple non-adjustable fixed hood

I have not seen a lighter hooded down jacket than the Montbell EX Light Anorak Hoodie. Only 1.4 ounces heavier than the Plasma 1000 above, but it has a hood! The Anorak Hoodie uses a slightly heavier down, and more of it in the fill, leaving me to wonder how they managed to keep the weight so low, while adding both features and warmth.

 

 


 

Arc’teryx Cerium SL Hybrid Hoody – $349

Weight:  215.45 g / 7.6 oz.
Fabric:  Arato (100% nylon) DWR finish
Insulation: 850-fill down / Coreloft (40g, 100g)
Fill Weight: 1.9 oz.
DWR: standard DWR treatment

  • Lightest down jacket in Arc’teryx’s Essentials collection
  • 850-fill down is surprisingly warm for how light it feels
  • Strategically placed synthetic insulation resists moisture
  • Water-resistant fabric protects down clusters from light moisture
  • Adjustments at hood and hem secure coverage
  • Stuff sack included inside one of the hand pockets

Blending actual down with varying degrees of synthetic loft creates a hybrid piece of attire capable of taking on a vast array of conditions.

A relatively light amount of fill combined with a minimalist build create a great insulator for high activity or layering. You do sacrifice warmth for weight with this jacket, so be ready to pair it with something if you are going to be stagnant while wearing.

 


 

 

Mountain Hardwear Ghost Whisperer Hooded Down Jacket – $350

Weight: 221 g / 7.8 oz.
Fabric: Whisperer 7D x 10D Ripstop (100% Nylon)
Insulation: Q.Shield™ Down 800-Fill, RDS Certified Down
Fill Weight: 79 g / 2.8 oz.
DWR: Down itself is treated for water resistance. ‘True’ 7×10 denier weave tightness naturally repels water

  • Low profile quilt pattern to create heat trapping down channels for extra warmth
  • Lightweight warmth makes it incredible for layering
  • Single interior toggle hem for easy adjustment on the fly
  • Soft, “Butter Jersey” cuffs have elastic binding to seal off cold and moisture
  • Zips into its own pocket for compact storage

The Mountain Hardwear Ghost Whisperer has been one of the most popular down jackets on the market for years, winning multiple ‘Best Of’, ‘Top Pick’, and ‘Gear of the Year’ awards from multiple outlets, over multiple years.

Though not the lightest down jacket available, the couple of ounces of extra weight translate to better function and performance. First, the shell is made from a woven Ripstop Nylon (7D threads one direction, 10D threads woven perpendicular), which increases durability and helps repel moisture naturally. Second, the down itself is water resistant.

As we all know, down does not insulate when it’s wet, so most down apparel companies use a DWR coating, which isn’t fully waterproof and can degrade over time, on the shell fabric. The Ghost Whisperer employs Q.Shield™ technology to treat the down itself, creating a hydrophobic coating on the feathers, allowing it to perform at a higher level for longer, in wet conditions. The difference to me is most noticeable in humid conditions. Even when there’s no precipitation, natural down can almost “wilt” in the baffles of your gear after prolonged exposure to wet, humid air, effectively compromising its ability to insulate. The hydrophopic down insulates much better in these conditions.

 

 

 


 

 

 

Nunatak JMT Jacket – $195

nunatak-jmt-jacket

Weight:  220 g / 7.8 oz (size L, no upgrades)
Fabric (Choice of):
Membrane 10D taffeta, 0.66 oz/yd
Robic Ripstop 7D, 0.74 oz/yd
Insulation: APEX by Climashield, a superior continuous filament synthetic insulation
Fill Weight: 2.2oz/yd – 75g/m²
DWR :
Pertex Quantum – factory DWR coating
Robic Ripstop – HH (hydrostatic head) of 1000mm

Think of this jacket at a really beefy insulated windbreaker. Nunatak recommends this piece for layering in mild conditions. Can provide some warmth on its own in high activity during spring and summer season outings.

Like most of the items from Nunatak this jacket is built to order, meaning the company lets you run wild with the options.

 

 

 


 

 

 

 

Montbell Thermawrap Jacket – $179

montbell-thermawrap

Weight:  241 g / 8.5 oz.
Fabric: Sleeve: 15-denier Ballistic Airlight rip-stop nylon
Body: 12-denier Ballistic Airlight rip-stop nylon
Insulation: Stretch Exceloft® synthetic insulation, 40g/m²
DWR: Standard DWR treatment
Compressed size: 4.7 x 7.9 in. / 12 x 20 cm

  • DWR treated zipper
  • 2 zippered hand pockets
  • 1 zippered chest pocket
  • Draw cords for waist adjustment hidden in pockets

The Montbell Thermawrap has been one of the most popular synthetic jackets on the market for years, winning multiple ‘Best Of’, ‘Top Pick’, and ‘Gear of the Year’ awards from multiple outlets, over multiple years.

The newer version uses 40g/m² of Stretch Exceloft® synthetic insulation, compared to the older models’ 50g/m², but is woven differently to achieve the same warmth while increasing breathability.

Montbell also improved the sleeve cuffs and added zippers to existing hand pockets and new chest pocket.

 

 

 

 


 

 

 

 

Arc’teryx Atom SL Synthetic Hoody – $229

Atom-SL-Hoody-Gator

Weight: 260 g / 9.2 oz
Fabric: Outer: Tyono™ 20 denier shell with DWR treatment – 100% nylon.
Underarms and side panels: Torrent™—84% polyester 16% elastane.
Insulation: Coreloft™ 40
DWR: Nu water repellent treatment

  • SL = Superlight. Superlight materials and design, emphasizing light weight and packability over durablity
  • Man-made insulation has quick dry times, durability and retains warmth when damp
  • Provides warmth comparable to a lightweight fleece for significantly fewer grams
  • Breathable, wind-permeable stretch fleece panels under arms and down sides, Moisture wicking, breathable, stretchy, jersey knit textile with a soft, brushed surface and a Polygiene® finish to manage odor
  • Coreloft™ Compact 40 insulation (40 g/m²). Highly crimped, multi-denier siliconized polyester yarn that has undergone a special process which reduces the thickness of the material by 50%, without reducing its insulation value by the same amount. Lightweight, breathable, thermally efficient 100% polyester fiber.

Very light but not great in very windy or cold conditions. Meant mainly for use during high exertion activities, but don’t expect to be comfortable with just this in sub 40’s or even sub 50’s with wind unless you are moving fast.

Used in a layering system, this is a great ultralight piece to throw in the mix. Using it as your only insulation in anything but mild conditions is doable, but not comfortable.

 


 

 

 Montbell U.L. Thermawrap Parka – $209

montbell-thermawrap-parka

Weight: 264 g / 9.3 oz.
Fabric: Sleeve: 15-denier Ballistic Airlight rip-stop nylon
Body: 12-denier Ballistic Airlight rip-stop nylon
Insulation: Stretch Exceloft® synthetic insulation, 40g/m²
DWR: Standard DWR treatment
Compressed size: 4.7 x 8.7 in / 12 x 22 cm

  • DWR treated zipper
  • 2 zippered hand pockets
  • 1 zippered chest pocket
  • Draw cords for waist adjustment hidden in pockets
  • Single Visor/Volume Adjustment on Hood

Pretty much the same as the Montbell Thermawrap Jacket but with a hood and the weight that comes with it.

 

 

 


Patagonia Micro Puff Synthetic Hoody – $299

patagonia-micro-puff-hoody

Weight: 264 g / 9.3 oz.
Fabric: 0.7-oz 10-denier 100% nylon ripstop Pertex Quantum®
Insulation: 65-g PlumaFill 100% polyester
DWR:
standard DWR treatment

  • Ultralight nylon ripstop Pertex Quantum® shell is water-resistant, windproof and treated with a DWR (durable water repellent) finish
  • Revolutionary PlumaFill insulation replicates the structure of down in a continuous synthetic insulation material, offering the warmth and packability of down but with the warm-when-wet performance of synthetic insulation
  • Innovative quilting construction complements the insulation by stabilizing and maximizing the loft of the PlumaFill strands with minimal stitching
  • Center-front zipper has wicking interior storm flap and zipper garage at chin for next-to-skin comfort
  • Two welted zippered handwarmer pockets; left pocket doubles as a stuffsack with a reinforced carabiner clip-in loop
  • Under-the-helmet hood construction is light and simple
  • Elasticized cuffs and hem seal in warmth

Using new PlumaFill insulation, the Micropuff starting racking up gear awards as soon as it was released. Not the lightest option out there, but possibly the most compressible. The jacket seems very delicate, but the 10D Ripstop is not as fragile as it seems.

64g/m² of PlumaFill provide more warmth for weight than lighter synthetics and Patagonia’s baffle design and sew method improve insulation performance.

Also, it’s just cute.

 


 

Feathered Friends Eos Down Jacket – $309

feathered-friends-eos-jacket

Weight: 300 g / 10.6 oz. (Medium)
Fabric:  Pertex® Quantum® brushed nylon with DWR (37g/m2)
Fill Power: 900+ Goose Down
Fill Weight: 3.7 oz.

  • Zippered hand warmer pockets
  • Sewn-through construction
  • Fixed low-profile hood
  • Elastic drawcord hem
  • Lycra cuffs and hood
  • Stuff Sack Included
  • Ethically-sourced 900+ fill power goose down

Feathered friends uses only the highest quality down on the planet and stuffs their jackets full of it.

The high loft and heavy fills create some of the warmest jackets on this list. No frills on this jacket, but the hood, drawcord, and full length zipper. All performance, minimal weight, no bullshit.

 

 


 

 

 

Nunatak Skaha APEX Ultralight Climashield Jacket – $200 +/-

skaha-apex-ultralight-climashield-jacket

Weight:  300 g / 10.6 oz (size L, no upgrades)
Fabric (Choice of):
Membrane 10D taffeta, 0.66 oz/yd
Pertex Quantum, 0.8 oz/yd 
Robic Ripstop 7D, 0.74 oz/yd
Insulation: APEX by Climashield, a superior continuous filament synthetic insulation
Fill Weight (Choice of):
2.5 oz/yd Climashield APEX – 85 g/m – light, compact, 2-3 season
3.6 oz/yd Climashield APEX  – 122 g/m – in betweener, solid 3 season
5.0 oz/yd Climashield APEX – 170 g/m – bulky, light 4 season use
DWR:
Membrane –  minimal water resistance
Pertex Quantum – factory DWR coating
Robic Ripstop – HH (hydrostatic head) of 1000mm

Ultra light and extremely warm for the weight, the Nunatak Skaha Jacket is one of the lightest synthetics, without sacrificing thermal efficiency.

Like most of the items from Nunatak this jacket is built to order, meaning the company lets you run wild with the options: zippers, pockets, hoods, fill weights, shell and liner fabrics, sleeve length, cuff material, and back length are all customizable!

 

 

 


 

Arc’teryx Mens Cerium LT Hybrid Hoody – $379

Weight:  305g / 10.8 oz.
Fabric: Arato™ 10 (100% nylon) DWR finish
Insulation: 850-fill European white goose down, Coreloft 100, Coreloft 80
Fill Weight:
3.4 oz.
DWR: standard DWR treatment

  • 850-fill goose down is light and compressible
  • Coreloft insulation for areas prone to overheating
  • Lightweight Arato shell with DWR treatment repels moisture
  • Adjustable, insulated StormHood protects head from wind and cold
  • Jacket stuffs into pocket for easy packing
  • Slim fit makes it easy to throw on under a shell

Never the cheapest option, but always high performing, Arc’teryx provides quality at a premium. Using some of the best down available and blending it with some of the warmest and most advanced synthetic insulation means this jacket will stay warmer in varied conditions.

The synthetic Coreloft stays toasty in moist environments and helps eliminate cold spots, shifting, and loss of loft, while the luxury down keeps everything warm and puffy. Arato shell with DWR treatment resists moisture well.

 

 

 


 

Nunatak Skaha Down Sweater, UL Version – $350

nunatak-skaha-down-sweater-ul-version

Weight:  326 g / 11.5 oz (size L, standard build)
Fabric (Choice of):
Membrane 10D taffeta, 0.66 oz/yd
Pertex Quantum, 0.8 oz/yd
Insulation: 900 fill power goose down, regular or moisture resistant Hyper-Dry down
Fill Weight (Choice of):  No overfill, 1oz overfill, 3oz overfill
DWR:
Membrane –  minimal water resistance
Pertex Quantum – factory DWR coating

Ultra light and extremely warm for the weight, the Nunatak Skaha Down Sweater is one of the lightest down insulation layers, without sacrificing thermal efficiency. This down sweater version of the Skaha doesn’t have as many options to choose from but you can still trick it out to suit your needs.

Like most of the items from Nunatak this jacket is built to order, meaning the company lets you run wild with the options: zippers, pockets, hoods, fill weights, shell and liner fabrics, sleeve length, cuff material, and back length are all customizable!

 

 

 


 

Zpacks Micro-Fleece Hoody – $149

fleece-jacket-front-l

Weight:  329 g / 11.6 oz.
Fabric: Made from soft, stretchy 4.2 oz/sqyd micro fleece

  • Full front zipper
  • Fitted hood
  • Hand pockets that close with zippers
  • Thumb holes
  • Adjustable elastic waist

Not very compressible, so a little bulky; around the size of a large thermos, a little bigger than a Nalgene bottle, but very warm and soft. I haven’t seen a lighter fleece jacket that’s this warm and well cut.

Great on its own but it excels as a part of a layering system, above or below down/synthetics, inside shells.

I love the thumb holes and the shape of the hood. Also, the fact that the zipper zips up to your nose, is awesome.

 


Arc’teryx Atom LT Synthetic Hoody – $259

Atom-LT-Hoody-Woad

Weight: 360 g / 12.7 oz
Fabric: Outer: Tyono™ 20 denier shell with DWR treatment – 100% nylon
Underarm and side panels: Polartec® Power Stretch® with Hardface® Technology panels for mobility and breathability
Insulation: 
Coreloft™ 60 insulation in the torso, arms and hood
DWR: Outer lining treated with DWR

  • LT = Lightweight. Durable, high performance with minimalist design to achieve light weight
  • Man-made insulation has quick dry times, durability and retains warmth when damp
  • Coreloft™ 60 (60 g/m²) insulation is made with highly crimped multi-denier siliconized polyester yarn, this lightweight, breathable, and thermally efficient, 100% polyester staple fiber is very compressible and has excellent loft retention
  • Polartec® Power Stretch® with Hardface® Technology—88% polyester, 12% elastane, 230 g/m². A four-way stretch fabric that allows for excellent athletic movement and good breathability to maintain comfort. Some products feature Hardface® Technology for a higher level of abrasion resistance

Almost the same as the Atom SL, the Atom LT uses Coreloft 60, which is a warmer and heavier insulation that the Atom SL’s Coreloft 40 fill.

 


Patagonia Nano Puff Synthetic Hoody – $249

patagonia-nano-puff-hoody

Weight: 363 g / 12.8 oz.
Fabic: Shell and lining: 1.4-oz 22-denier 100% recycled polyester
Insulation: Insulation: 60-g PrimaLoft® Gold Insulation Eco 100% polyester (55% post-consumer recycled content)
DWR: Standard DWR treatment

  • 60-g PrimaLoft® Gold Insulation Eco, with 55% postconsumer recycled content, is water-repellent, highly compressible and maintains 98% of warmth, even when wet
  • Brick quilting pattern with horizontal quilt lines on side panels stabilizes insulation and uses durable thread for abrasion resistance
  • Center-front zipper has wicking interior storm flap and zipper garage at chin for next-to-skin comfort
  • Two zippered handwarmer pockets have cleanly finished zipper garages; zippered internal chest pocket doubles as a stuffsack with a reinforced carabiner clip-in loop
  • Under-the-helmet hood construction is light and simple
  • Drawcord-adjustable drop-tail hem seals in warmth

Not as light as the Micropuff, but warmer and far more durable. The Nanopuff uses 60-g PrimaLoft® Gold Insulation Eco 100% polyester, which is made from a majority post consumer recycled content, is heavier, and provides more insulation.

The shell is a 1.4 ounce 22D polyester (versus the Micropuff’s 10D Ripstop), which is very durable stuff that should take a beating and last a long long time.

 

 


 

 MontBell Mirage Hooded Down Parka – $379

c_2301185_bk

Weight: 363 g / 12.8 oz.
Fabric: 7-denier Ballistic Airlight rip-stop nylon shell & lining
Fill Weight: 5.3 oz.
Insulation: 900 Fill Power EX Down
DWR: Standard DWR treatment
Compressed Size (approx.): 5.3 x 9.5 in. / 14 x 24 cm

  • Box construction
  • 2-way adjustable fixed hood
  • 2 zippered hand warmer pockets
  • Draw cords for waist adjustment hidden in pockets
  • 2 internal drop-in pockets
  • Adjustable alpine cuff
  • Stuff sack included

With twice the fill weight of most other down jackets on this list, but only a few ounces heavier, this is your go to for Ultralight in more extreme conditions. While most of the lighter weight jackets perform well to a point, most are better reserved for 1 – 3 season use.

The Mirage maintains UL weight, while providing enough warmth to be used during that snowy 4th season. Used as part of a layering system, you can take this jacket into some very extreme weather comfortably, without much of a weight penalty.

 


 

Patagonia Hyper Puff Synthetic Hoody – $299

patagonia-hyper-puff-hoody
Weight: 524 g / 18.5 oz.
Fabic: 1.1-oz 100% nylon stretch ripstop Pertex Quantum®  (Shell and lining fabric is certified as bluesign® approved)
Insulation: 100-g 100% polyester HyperDAS insulation
DWR: Standard DWR treatment

  • Lightweight, 2-way-stretch nylon ripstop Pertex Quantum® shell is durable, water-resistant, windproof and treated with a DWR (durable water repellent) finish
  • Innovative synthetic 100-g HyperDAS insulation packs down small but delivers big loft and warmth by creating plenty of dead air space (DAS)
  • Engineered patterning and variable quilting provide maximum articulation for deep warmth and unhindered movement
  • Full-length zipper with internal wind flap and fold-over zipper garage for next-to-skin comfort
  • Simple, articulated, helmet-compatible hood with internal elastic stitching, visor and single-pull drawcord to adjust overall volume and peripheral vision
  • Two zippered, insulated handwarmer pockets; large interior mesh drop-in pocket; one exterior zippered chest pocket
  • Elasticized cuffs and discreet drawcord at drop hem seal in warmth; stuff sack for easy storage

At over a pound, we are starting to get out of the Ultralight realm with the Patagonia Hyper Puff, but the features and performance maintain this jacket’s relevance and place in a backpacker’s gear closet.

Heavy 100g/m² HyperDAS insulation provide tons of warmth, utilizing ‘Dead Air Space’ between the synthetic fibers to trap warm air. The design and cut of the jacket allow full articulation during any activity.

Zipper flap, zipper garage, insulated pockets, internal easy-access drop in pocket, exterior chest pocket, drawcord hem all add luxury to this 3rd and 4th season piece.

 

 


 

Patagonia Grade VII Down Parka – $899

patagonia-VII-down-parka
Weight: 675 g / 23.8 oz.
Fabric: Front shell: 1.2-oz 15-denier 100% nylon ripstop with a light DWR (durable water repellent) finish.
Side and back shell: 1.2-oz 20-denier 100% nylon with a light DWR finish.
Lining: 0.85-oz 15-denier 100% nylon ripstop Pertex® Quantum built with Y-shaped filament technology and a DWR finish.
Insulation: 800-fill-power 100% Advanced Global Traceable Down (goose down certified by NSF International from parent farm to apparel factory to help ensure the birds that supply it are not force-fed or live-plucked)

  • Light yet durable 100% nylon shell fabrics maximize wet-weather protection with a light DWR (durable water repellent) finish throughout, and glued-baffle construction on arms, shoulders and chest
  • Fully baffled construction and differentially cut shell and liner keep down lofted and eliminate cold spots; elasticized stitch on liner at side panels pulls jacket into the body
  • Alpine helmet–compatible, baffled hood has a single-pull drawcord and high-loft draft collar around the neck; 2-way center-front Vislon® zipper is backed with kissing draft tubes
  • Exterior pockets: two large chest pockets with zipper garages, and two large hand pockets with stiffened welts for easy access; all pockets have down insulation on both sides of pocket bag to retain warmth when pockets are open
  • Interior pockets: two catch-all pockets on each side of the front torso have stretch mesh for draining snow melt; right-rear interior pocket has small stash pocket with keeper-loop for retaining self-fabric stuffsack
  • Elasticized stitch at the cuff opening sits gently on the wrist, locking in heat and allowing the sleeve to be easily pulled down over gloves, or pushed up at brew stops
  • Hem-cord routes through mini snowskirt and is located several inches above jacket hem to cinch toward body without draft spots

Made for mountaineering and extreme cold weather adventures, this is the warmest and puffiest jacket of the group. It is also the heaviest. Certainly not Ultralight, but still incredibly lightweight for all of its features, the Patagonia Grade VII is incredibly warm, high performing, full of features, and still weights less than two pounds!

This is a niche piece of gear with a very high price tag. Honestly, for what it can handle the price is more than fair; you can spend a lot more on less featured jackets that don’t provide as much warms.

You would never bring a jacket like this on most thru hikes, but on extreme treks, high altitude base camps, or static belays, jackets like this will save your life.

 

 

 

 

 

 

 

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