Jöttnar Fenrir Down Jacket Review

In this review UKC regular gear tester Toby Archer keeps warm wrapped up in the Jottnar Fenrir Down Jacket - taking it out in some pretty damp weather, but that is what it is designed for, right?

 Last winter I really enjoyed reviewing the Jöttnar Fjorm down jacket, a wonderfully designed and ferociously warm down jacket good for belaying in the most horrible conditions. Hence it was a pleasure to then be asked to review Jöttnar’s second and rather different style of down jacket, the Fenrir (and, no, the Jöttnar chaps clearly don’t intend on making any of their product names more pronounceable!).

At 394 grams on my scales, the Fenrir weighs less than two thirds of the Fjorm and packs considerably smaller too. It is a hooded, micro-baffled down jacket of the type that has become rather popular and, indeed, fashionable over recent winters, but with plenty of technical features that show Jöttnar is still targeting the technical mountain market with their designs.

A simple hood that can be pulled over other hoods but only just fits over a helmet.  © Toby Archer
A simple hood that can be pulled over other hoods but only just fits over a helmet.
© Toby Archer
Used as a belay jacket over a shell on cold and very windy day winter climbing.  © Toby Archer
Used as a belay jacket over a shell on cold and very windy day winter climbing.
© Toby Archer


Firstly, the cut is well worth noting. The Fenrir is a trim cut. I have used it as a belay jacket over a shell (Jöttnar’s own Bergelmir); it does go over but only just and for me at least, once I have some layers underneath its a bit too tight to pull down over my hips and bum. Wearing a harness only compounds this issue. Unlike the Fjorm, the cut suggests that the Fenrir’s isn’t really designed as a winter pull-over-everything belay jacket.

Indeed it fits more easily under the Bergelmir, although with the amount of sweat I produce when climbing or walking hard, I have never felt the need or really got the point of using down as a midlayer. Of course others may differ on this, and with the Fenrir using hydrophobic DOWN-TEK treated goose down, it can be expected to work better under a shell than thin down jackets did just a few years ago.

I have, though, found the Fenrir great to pull on over a softshell when rock climbing and will definitely be taking it as lightweight belay jacket for multipitch mountain rock routes in the future.

The jacket is rather spartan in terms of features accounting for its low weight and bulk. There are two zipped hand warmer pockets (I would happily live with 10 grams more weight in order to have an internal, zipped security pocket for car keys and the like); the cuffs are a simple elasticated design which works well, sealing warmth in but not being too tight.

The hood is also a simple, non-adjustable design with the same lycra hemming as the cuffs. If you don’t have the main zip fully up, you can pull the helmet over a climbing helmet (at least with a relatively low profile foam helmet) but clearly it isn’t a hood designed to be used over a helmet like the excellent wired one on the Fjorm.

When not wearing a helmet, and despite not having adjustment cords, I found the Fenrir’s hood works rather well - the main zip has a good soft chin guard and with that fully zipped up and the hood on, the jacket has cosy and protective vibe to it. The Fenrir does have a drawcord on its hem to keep it snug around your bum and hips.

Jöttnar calls the Fenrir a hybrid jacket as some of the jacket’s insulation channels are filled with synthetic insulation rather than down. Jöttnar have limited the synthetic insulation to around the hem of the jacket, the wrists and in the collar where you may well be breathing onto it. perhaps more synthetic insulation isn’t really necessary when the Fenrir’s shell seems pretty water resistant anyway, plus this is backed up by the hydrophobically treated down.

The company’s website actually says the Fenrir is designed for “cold and damp conditions”, something that not many down jacket makers would have said even just a couple of years ago before hydrophobic treatments became the norm.

A down jacket for damp conditions? With a good DWR treated shell and hydrophobic down, maybe.  © Toby Archer
A down jacket for damp conditions? With a good DWR treated shell and hydrophobic down, maybe.
© Toby Archer

I’ve now worn the jacket while out on the eastern edges of the Peak in December, while trying to snatch some routes between wind-driven snow, sleet, hail and rain showers and have been impressed by the jackets ability to resist moisture. Previously I wouldn’t have thought of down jackets being much cop for that sort of thing, but the Fenrir has been holding its own.

How much this is the DWR coating on the jacket’s shell and how much it is the DOWN-TEK treatment on the down is hard to say, but overall, it doesn’t really matter - it works and, surprising myself a little, I would stand by Jöttnar’s claim of the jacket being for “cold and damp conditions”.

On these quick solo missions to get some routes in, I’ve actually found myself climbing in the Fenrir quite a lot. When climbing on my own I tend to favour easier crack climbs where I know I can lock myself into the route with secure handjams and finger locks. This does mean though you can’t worry too much about scuffing your jacket arms in an effort to get a jam deep in some dark gritstone crevice!

The Jöttnar Fenrir, making the worst of the winter season a bit more bearable!  © Toby Archer
The Jöttnar Fenrir, making the worst of the winter season a bit more bearable!
© Toby Archer

If I hadn’t been reviewing the Fenrir I probably would have been a bit reticent to find out how abrasion resistant it is via this method - but in the name of science (well, gear reviewing at least) I have been up to my elbows wearing it on numerous routes at Stanage, Burbage and Rivelin.

Overall, it seems to be superbly scuff resistant for such a lightweight jacket and this bodes well for anyone thinking the Fenrir might make a good alpine rock belay jacket or similar.

In conclusion, the Fenrir is eminently wearable jacket that is a lot tougher at standing up to the elements than you might expect from a lightweight downie. Pulled on over a shell jacket in very strong winds and sub-zero temperatures on the top of Helvellyn, the jacket offered plenty of quick warmth but with only 112 grams of down filling (albeit very high quality 850 fill down), it would be unrealistic to think of it as a full-on belay jacket; besides anything else the hood is a compromise if you are wearing a helmet. Better is to think of the Fenrir as really multipurpose and lightweight booster jacket for all sorts of other outdoor sports.

Mine will be stuffed into the pack for spring-time backpacks and hill walks; it will continue to come rock climbing for quick warmth between pitches, particularly when the cliff involves a good walk to get too and the lack of weight is a plus. It would also make a great lunch-stop jacket for ski tours in not too grim weather.

At an RRP of £200, the Fenrir isn’t even particularly expensive for a jacket in its class. Down jackets are always a bit of investment, but I think the Fenrir will give many years of useful service for any keen climber or outdoors-person.

Fenrir Jottnar  © UKC Gear
What Jottnar Say:

A hybrid, hooded, lightweight, 850 Fill Power hydrophobic micro-down jacket for use as a mid or outer layer in cold and damp conditions.

Featuring water-repellent down, applied via nano-technology by our US based partner DOWN-TEK™, this jacket maintains loft and insulation irrespective of conditions. Unlike inferior versions, our water repellency does not wash out.

A lightweight, robust rip-stop face fabric allows the down to achieve full loft and its Durable Water Repellent (DWR) finish resists rain. Potential wet-out zones at the cuffs, hem and collar are reinforced with NEUTRON™ synthetic insulation meaning even less fear of moisture.

Highly versatile, Fenrir is at home in the vertical as it is in everyday use.


For more information visit the website

Support UKC

As climbers we strive to make the kind of website we would love to visit, with the most up-to-date news, diverse and interesting articles, comprehensive gear reviews, breathtaking photographs and a vast and useful logbook system. As a result, an incredible community has formed around the site - we’ve provided the framework but it’s you who make the website what it is today. If you appreciate the content we offer then you can help us by becoming an official UKC Supporter. This can be a one-off single annual payment or a more substantial payment paid monthly or yearly which includes full access to Rockfax Digital and discounts on Rockfax print publications.

If you appreciate then please help us by becoming a UKC Supporter.

UKC Supporter

  • Support the website we all know and love
  • Access to a year's subscription to Rockfax Digital.
  • Plus 30% off Rockfax guidebooks
  • Plus Show your support UKC Supporter badge on your profile and forum posts
UKC/UKH/Rockfax logo

23 Jan, 2015
850 U.S. or EU?
23 Jan, 2015
I'm currently dithering between the Fenrir, Fjorm and alternatives, so this is in the nick of time, thanks! Particularly impressed with the durability/weatherproofness that you mention, but worried by the "trim cut" (I'm not the thinnest of people). Is it a "trim cut" as in only for those of slender waist, or is it a "trim cut" as in 'don't expect to wear the size that should be right by the numbers over lots of layers'
24 Jan, 2015
I've found this to be more generous round the middle than the Mountain Equipment light down jacket I had previously
25 Jan, 2015
Was wearing the Fjorm yesterday and glad of it - it a significantly warmer jacket, but of course at the cost of increased weight and bulk… More the latter I would say, but it is slimmer at the waist/bum than some other jackets. I'm about 32/34 waist but I think I have a reasonably prominent bum (I was once even assured this was a good thing by an attractive Australian lady!) but this does mean that I have to pull the Fenrir down over my bum to make the best use of its length and it still has a tendency to ride back up to just below waist height. That's not a problem with the Fjorm or the Bergelmir shell, all in medium.
25 Jan, 2015
Good question, I'll ask as I don't know! Do you think it makes a noticeable difference?
More Comments
Loading Notifications...
Facebook Twitter Copy Email LinkedIn Pinterest