Down Jacket

Insulated jackets for cold, dry days

A down jacket traps warmth in lofted filling rather than in thick fabric, which is why it feels light for the heat it holds. The range gathers insulated winter and hiking jackets for men and women, ski cuts, and a heated option, in weights that suit a British winter rather than an expedition. The decision is mostly about how wet the days are and whether the jacket is worn while moving or while standing still. Where the same core warmth is wanted without sleeves, a down vest covers the torso and leaves the arms free to work.

How does lofted insulation keep heat in?

The filling itself does nothing. What warms the body is the still air held between the fibres, so the thickness of that trapped layer, not the weight of the jacket, is what matters. Compress it under a rucksack strap or a tight shell and the warmth disappears at that spot, which is why the shoulders are the first place the cold gets through. The same logic explains why a jacket packed tight for months loses loft and needs shaking out before a cold trip.

Which filling suits an insulated jacket?

• Warmth for weight: down loft gives more heat per gram, which shows on a long walk-in where every item is carried.
• Behaviour when wet: down clumps and stops lofting once soaked, synthetic filling keeps part of its thickness and dries far faster.
• Packed size: down compresses smaller, so it disappears into a day pack for use at rest stops.
• Care: synthetic tolerates ordinary washing, down needs a gentle cycle and a long tumble with dryer balls to break up the clumps.

Fill power and fill weight are two different figures, and both appear on product pages where the maker publishes them. Neither is worth guessing at from a photograph.

Should an insulated jacket be worn while walking?

Usually not uphill. Bodies produce a surprising amount of heat once moving, and a warm jacket zipped up on a climb ends in a soaked base layer that chills at the top. The pattern that works is to walk slightly cold in a fleece or shell, then put the insulated layer on the moment the walking stops. A softshell jacket covers that moving-and-breathing role better than any lofted jacket can.

What happens in the rain?

Most insulated jackets have a shower-resistant face fabric, not a waterproof one, so persistent rain reaches the filling and flattens it. Layering a waterproof jacket over the top keeps the loft dry and adds a windproof shell at the same time. Anyone who spends long periods stationary in cold and damp conditions might also look at a heated jacket, where an element adds heat instead of relying on body warmth alone.

How is loft kept alive?

Store it hanging or loosely folded, never crushed in a stuff sack between seasons. Wash rarely, on a gentle cycle with a cleaner made for insulation, and dry fully, since damp filling stays flat and smells. Small tears in the face fabric are worth patching straight away, because filling escapes through a hole faster than expected.