Which Filling?

Things used to be simple here: down in cold dry conditions when weight and pack size are a priority, synthetic in cold and damp climates, where down tended to collapse and lose effectiveness if it got wet. Well not any more, there are plenty of halfway choices, but to help you narrow things down, here’s a look at different options, and how they work.

How warm a jacket you need is down to you. In general, the warmer the jacket, the bulkier and heavier it’ll be. If you run remotely warm, most insulated jackets will be too warm for most active use unless it’s very cold as well as not being very breathable. There are jackets designed to be used on the move, often with more breathable fabrics though they tend, like the Patagonia Nano Air, to sacrifice weather protection as a result.

Water Resistant Down

First introduced a couple of years ago in the UK by Berghaus, water-resistant or hydrophobic down has a water repellent treatment that means it’ll resist damp for longer and keep you warmer when it is damp. It’ll also dry faster than untreated down and retain around 90% of its original loft once it dries out.

We’ve found the best stuff works very well, but we’d still look at it primarily as an insurance policy rather than a wet conditions option. It does give peace of mind though. Brands using water-resistant down include: Berghaus, Jöttnar, Mountain Equipment, Montane, MHW and Rab.

Conventional Synthetics

The best synthetics like Primaloft are highly water-resistant meaning they maintain more warmth when damp, don’t collapse and dry fast. They’re easier to care for than down as well with no special washing or drying techniques needed. Teamed with a water-resistant, coated outer, they make great options for cold and wet conditions like, for example, classic Scottish winter days. the downside is that synthetics aren’t as warm or small packing for their weight as down.

Primaloft is perhaps the best known option out there and very impressive, but the likes of ME, Arc’teryx, Haglöfs and others produce highly effective own-brand synthetic fills.

Primaloft Down Blend

Finally, Primaloft has mixed water-resistant down and synthetic fibres for another ‘best of both worlds’ concoction called Down Blend – not to be confused with instant coffee. In out tests it offered close to down warmth and weight ratios, but was superb when it got wet and recovered completely far more quickly than down. We’re impressed so far.

Zoned Fills

Finally, a few brands are mixing zones of different fills. Jöttnar and Arc’teryx both use synthetic fill areas in potential ‘wet-out zones’ of their down clothing, while Berghaus has taken things a stage further with body-mapped hybrid garments like the Ulvetanna Hybrid above, which use detailed research to place more breathable synthetic panels in some areas and warmer, down-filled ones in others. Interesting stuff especially if you run hot.

The Bottom Line

Broadly speaking, we’d still pick down for cold and dry environments, but there’s no reason not to use water-resistant down, particularly as over the course of a long trip, it can help to reduce the gradual deterioration in performance thanks to gradual condensation build-up inside the filling.

Similarly, for cold and damp or wet conditions, synthetic fills still make good sense, particularly combined with a highly water-resistant fabric with minimal seams and stitching to let water in, one of the advantages that traditional synthetics still have over the new ‘down-like’ varieties. The downside is that you will carry more weight and bulk for the warmth levels.

Which leaves us with the blends and the down-like synthetics. We reckon they’re a good compromise between the two and will particularly appeal if you like the puffy, baffled look of down, but want more reassurance in damp conditions. Primaloft Down Blend is similarly impressive and the Gold version comes close to down weight and bulk.

Suits You Sir…

Broadly speaking, insulated jackets take two forms: the belay or ‘overlayering’ jacket that’s cut big to fit over other layers including shell jackets and maybe a harness for planned and unplanned stops and chilly belays. And the slimmer cut jackets which are designed to be worn either as an outer layer or possibly, in severe conditions, layered under a shell jacket.

There is some cross-over, but it’s a good idea to consider how you’re planning to use the jacket before buying. Some sleeker cut jackets won’t fit over other layers so you may need to size up for overlayering use, or simply look elsewhere.

Features

Here are a few points to bear in mind when buying.

Hoods

If you want a helmet hood, make sure it really will fit over your helmet with your neck length and allow you to move your head freely. Ideally it should also fit snugly over a bare or beanied head for non-helmet use.

Hand-warmer Pockets

Look for insulation on the outside of the pockets so they will actually keep your hands warm. If you’re going to use a harness with the jacket, make sure the pockets sit so you can still use them. Big chest pockets works well here.

Zips And Pulls

Chances are you’re going to be using the jacket with gloves on, so look for smooth-running zips – we like YKK Vislon for this reason – with positive zip-pulls you can grab even with winter gloves.

Adjustments

Many lighter jackets have simple elasticated, Lycra-bound cuffs and even hems, but you need to make sure they will still seal in warmth or you’ll have a nasty draught to deal with when you least need it. Glove friendliness is important here too.

Mobility

If you’re planning on climbing or just doing stuff in your jacket, make sure the sleeves in particular aren’t restrictive. Some jackets use lighter fills or construction in the sleeve area for just this reason.

Stuffing

We’r big fans of jackets that stuff neatly into their own pockets for the simple reason that there’s no stuff-sac to lose. If a stuff-sac is suppled, try looping it onto something in the jacket to stop it wandering off and disappearing for ever. Don’t ask how we know…

Green Considerations

There’s general concern over animal cruelty issues around down production, but most specialist outdoor brands source their down as ethically as possible, with Mountain Equipment and its Down Codex project at the forefront of traceability. If in doubt, research and ask the brand.

On the synthetic side, many brands now use recycled materials in their insulation and shell fabrics along with PFC free DWRs and water-resistant down treatments like Jöttnar’s DownTek down and Primaloft’s Down Blend. Scandinavian brands like Haglöfs and Fjällräven are particularly committed to sustainable practices, but again, research before buying.

Box-wall construction sits the down in square channels with walls between them which eliminates cold spots, but is heaver and more complicated to produce. Some brands, Jöttnar and Montane for example, use box-wall in the body for ultimate warmth, but with stitch-through sleeve construction to save weight.

Berghaus takes things further again with differentiated zoned areas using different sizes of down compartment to optimise warmth in various body areas. Clever stuff and works well.

More Information

For individual jacket reviews see: Best Down And Synthetic Insulated Jackets 2016.